My boiler is short cycling

[zuffy]

I have a Weil-McLain EG gas boiler that provides steam heat. I bought the house last August. Started to turn on the heat probably in late Oct or early Nov. I would leave the thermostat at 68 degree all day because my grandmom is in the house. I don't remember the boiler would ever short cycling like now. It would fire up for 3 minutes every 15-18 minutes but there is no heat to the radiators. If I push the thermostat up 69 or 70, then I can feel the heat is coming out from the radiators. Or if I let the room temperature drop to 66-67 and then set the thermostat to 68, then I can feel the heat coming out from the radiators.

Over the weekend, I took the air vents out and rinse them and shake out any particles. Some of them seem very old. Also, I made sure all the valves in the radiators are fully open. I think it was back in mid-Nov or late-Nov where I drained the boiler. The water in the glass tube looked fine but the water coming out from the drain was close to dark brown. Not sure if the draining has anything to do with it.

Also, last night, I changed the Honeywell thermostat from the default 6 cph to 3 cph. Do you think that will help?

I need help. When I saw the last gas bill, it was quite expensive - $662.45 for 395 thermals from Keyspan. Almost double my previous bill.

[plumberscrack]

Obviously there is something wrong. 3 minutes is not enough time to produce steam. You should have a professional have a look.

Changing the CPH on the tstat might help but I believe something else is wrong. Steam boilers need to be blown down all the time. Once a week during a cold season not every few months. Replace the steam vents and blow down the boiler and see how it does.

[NHMaster3015]

Can you shoot over a photo of the boiler and controls.?

[NHMaster3015]

These are the possible causes of your problem. Some you can check, and others you may want to call a service tech for. The thermostat is out of calibration.If it is, the burner will be bouncing on and off. Make sure you use an ammeter when you're checking the calibration. Don't guess at that anticipator's setting.
Check, too, to see if the thermostat has a mercury switch. If it does, make sure the thermostat hangs level on the wall. And check to see if the thermostat is in a cold draft, or if it's hanging on a poorly insulated, outside wall. Make the necessary corrections.


The boiler is oversized.You're supposed to size the boiler and fire the burner to the connected piping-and-radiation load. In the boiler manufacturer's literature, they call this load the D.O.E. Heating Capacity. If your boiler is too big, its ability to produce steam will exceed the system's ability to condense steam. The burner will short-cycle.
You may be able to solve the problem by down-firing the burner, but be careful when you try this. You may down-fire to a point where the flue gases begin to condense. Fire only to the connected load.


The boiler is properly sized, but overfired.If there's too much fire, you'll get lots of steam in a hurry. That will quickly raise the boiler pressure and short-cycle the burner off the pressuretrol.
Raising the pressuretrol setting isn't a good solution to this problem. Over-firing will also throw water up into the piping. This leads to water hammer, uneven heating and short-cycling.
Check your gas pressure, or your nozzle size (on an oil-fired system).


The boiler is making wet steam.Check the near-boiler piping against the manufacturer's specifications. If the piping can't separate the water from the steam, the water will cause the steam to condense, and the burner will short-cycle.
Check the boiler water's pH and its cleanliness too. You may have to clean the boiler and the system and balance the pH with chemicals.


The steam traps aren't working.Two-pipe steam is like a ladder. Each radiator is a rung on that "ladder," and at the end of each rung you'll find a steam trap. Part of the trap's job is to keep steam from entering the no-pressure side of the ladder. If even one trap fails in the open position, steam will jump across and pressurize the air on the other side of the system. As the pressure builds, the burner will short-cycle on the pressuretrol.
Float & thermostatic and bucket traps serve the same purpose at the ends of the mains, and at the base of risers. If they fail in the open position, or, with bucket traps, if they lose their prime water, steam can move into dry return lines and cause burner short-cycling and water hammer.
Trap maintenance is essential.


The air vents aren't working.If they're not, the system will trap air and pressurize it. Remember, steam and air are both gases, but steam is lighter than air, so the two won't mix.
When the steam heads down a pipe, it pushes air ahead of itself. If the air can't get out at the end of the pipe (through a vent), the steam will just compress it. The pressure builds, and the burner shuts off on the pressuretrol. The burner short-cycles, but that's not your only problem. The building also remains cold because the radiators and mains are filled with air instead of steam. Usually, someone comes along and raises the pressure. They mean well; they're trying to solve the short-cycling and give the folks some heat. But the higher steam pressure just compresses the air a bit more. It usually doesn't help the lack-of-heat problem. It just raises the fuel bill.
Check the air vents, and clean or replace them where necessary.


The pressuretrol or the pigtail is clogged.If there's sludge in the pressuretrol or the pigtail that connects the pressuretrol to the boiler, the burner will short-cycle. The pigtail's job is to fill with water and keep the steam temperature from reaching into the pressuretrol. A pigtail is a natural collector of sludge. If you can't clean the pigtail (a tough job), replace it.


The pressuretrol has a mercury switch and it isn't level.Some pressuretrols have mercury switches. If the pressuretrol isn't plumb and level, the mercury might trip too soon. That can cause the burner to short-cycle.
If the pressuretrol sits on a pigtail, make sure the curved part of the pigtail faces front to back (when you're looking straight at the pressuretrol). If you have the curved part turned from side to side (so you can see through the circle when you're looking straight at the pressuretrol), the burner might short-cycle. This is because the curved part of the pigtail straightens a bit when heated. As it straightens, the pigtail tips the mercury and stops the burner. When you turn the pigtail so that it faces front to back, it tips the pressuretrol from front to back, but not from side to side. This doesn't affect the mercury switch.

[zuffy]

These are old photos. Let me know if you need more shots.

http://mysite.verizon.net/zuffy/boiler.jpg
http://mysite.verizon.net/zuffy/control.jpg
http://mysite.verizon.net/zuffy/gauge.jpg
http://mysite.verizon.net/zuffy/lowwater.jpg
http://mysite.verizon.net/zuffy/psi.jpg
http://mysite.verizon.net/zuffy/feeder.jpg

[zuffy]

Obviously there is something wrong. 3 minutes is not enough time to produce steam. You should have a professional have a look.

Changing the CPH on the tstat might help but I believe something else is wrong. Steam boilers need to be blown down all the time. Once a week during a cold season not every few months. Replace the steam vents and blow down the boiler and see how it does.

I have 3 bedrooms and a bath in the second floor. The master room and the second room has a single pipe fined radiator about 3.5' wide. They look like using a fairly large vent hole. The third bedroom radiator is about 2.5' with a tiny air vent. Can I put in an air vent with a larger hole?

Second question, how do I tell what size are the existing air vents?

[zuffy]

As to the model of the boiler, it's either the Weil-McLain EG 40 or 45 gas boiler. The thermostat is a Honeywell T8600D.

[HVAC HAWK]

1 is the water at the right level and there is a re set on the low water cut off try this

2 if you jump out the t stat does the boiler stay running

3 is the damper on the flue pipe opening

4 does the flame look the same as it did last time it was running good

5 check the pressure switch

some thing is telling it to shut down and it is not even running long enough for the water to get hot

and you need to run a pipe off the relief valve down to the floor ,if it goes off and you are standing close you will get a face full of hot steam :eek::eek:

let us know if you checked this stuff

[zuffy]

1 is the water at the right level and there is a re set on the low water cut off try this

Yes, the water is at the right level. It's at least half fill.

2 if you jump out the t stat does the boiler stay running

It will stay running but once it gets up to the set temperature, it will do it's short cycling from what I can remember

3 is the damper on the flue pipe opening

Yes, it open each time the boiler comes on. I can hear it.

4 does the flame look the same as it did last time it was running good

I have no idea

5 check the pressure switch

some thing is telling it to shut down and it is not even running long enough for the water to get hot

Which one is the pressure switch or where is it?

and you need to run a pipe off the relief valve down to the floor ,if it goes off and you are standing close you will get a face full of hot steam :eek::eek:

Someone pointed that out to me when I got the house. All taken care of.

let us know if you checked this stuff

Thanks for the help

[NHMaster3015]

If all that stuff checks out, go to the part in my post about cleaning the pig tail.

[zuffy]

Which one is the pig tail? Is that the big pipe in the boiler? I remember I open that valve when I was draining the boiler. I think like 2lb of black crap came out.

[HVAC HAWK]

the pig tail is the small brass pipe that does a loop

the picture that you have marked control is your pressure setting and the small pipe is a pig tail

[HVAC HAWK]

after it heats up the first time is it making steam before it shuts down

the valve with the yellow handle next to the glass tube ,put a bucket under it and open it if nothing comes out wait untill the boiler heats up then open it . this is a skimmer valve and if the water gets oil or a lot of stuff in it it will not make steam , so you need to skim this stuff off .

[DuckButter]

Steam systems run best at a max of 2psi.
I noticed in the pics that the guage was at or near zero, was it operating at the time?
Also I noticed the pressuretrol was all the way down to .5, maybe a little increase might slow the frequency it cycles..don't go more than 2 psi, in fact only a small amount per try until it either stops short cycling or you're @ 2psi on the boiler guage when it shuts off.

My #1 guess is whats already been mentioned, the pigtail feed to the pressuretrol might be clogged, thats very common.
Usually it's good measure to replace both pigtail and presuretrol at the same time while you're at it.

IF any of this sounds confusing, please consider getting a pro to look at it, if you mistake one thing for another and accidently alter/damage a safety, you could create a hazardous situation.

[zuffy]

When you said clean the pig tail, you meant inside the tube right?

OK, I turn the thermostat up 1 degree to 69 to get the boiler firing. I have left the thermostat to 68 since last night. When I got home at 7pm, I have not seen the boiler coming on and it's 9pm. Also, the radiators were cold too when I got home.

The boiler has been running for the last 15 minutes since I set it to 69 degree. Steam are coming up at the radiators and boiler is still firing.

[zuffy]

Steam systems run best at a max of 2psi.
I noticed in the pics that the guage was at or near zero, was it operating at the time?
Also I noticed the pressuretrol was all the way down to .5, maybe a little increase might slow the frequency it cycles..don't go more than 2 psi, in fact only a small amount per try until it either stops short cycling or you're @ 2psi on the boiler guage when it shuts off.

My #1 guess is whats already been mentioned, the pigtail feed to the pressuretrol might be clogged, thats very common.
Usually it's good measure to replace both pigtail and presuretrol at the same time while you're at it.

IF any of this sounds confusing, please consider getting a pro to look at it, if you mistake one thing for another and accidently alter/damage a safety, you could create a hazardous situation.

The Honeywell control was never touched. It has always been at the same level. There is line that says 2 and below is .5, the indicator is in between.

If the Honeywell thing is the pressuretrol, I will get a pro to replace it if he agree that is the problem. I know better than to try to fix something I'm not comfortable doing.

Thanks for the help.

[zuffy]

the valve with the yellow handle next to the glass tube ,put a bucket under it and open it if nothing comes out wait untill the boiler heats up then open it . this is a skimmer valve and if the water gets oil or a lot of stuff in it it will not make steam , so you need to skim this stuff off .

Should I still do this now that the boiler stop firing? Steam is coming up in all radiators.

[zuffy]

OK, I open the valve with the yellow handle. About 6-8oz of dark brown water/dirt came out.

[zuffy]

Since I have turn the thermostat to 69 @ 8:55pm, the boiler was firing till 9:10pm. It stayed off until 9:37pm. It went on for about 3 minutes.

So should I keep the cph to 3 or change it back to the default 6? Seem like 3 cph is working better, less short cycling so far.

[zuffy]

Last comment before I head to bed. I took the Honeywell pressuretrol off. I see that the pig tail is filled with water. Is that normal? I tried to take the pig tail off but can't. I will let a pro replace it if needed.

[NHMaster3015]

Since I have turn the thermostat to 69 @ 8:55pm, the boiler was firing till 9:10pm. It stayed off until 9:37pm. It went on for about 3 minutes.

So should I keep the cph to 3 or change it back to the default 6? Seem like 3 cph is working better, less short cycling so far.


OK, think it's sorted out now. Change the thermostat. Get hold of one of the new mercury free, solid state ones. Honeywell, Robertshaw, ect. Make sure when you install it you read the instructions and set the heat anticipator where the directions say too.

[NHMaster3015]

Honeywell T8775A-1009 would be a good choice $ 50 - $75 bucks

[zuffy]

You're saying the thermostat is bad? The one you recommended is non-programmable. If I am replacing it, I would like somthing similiar to what I have now, which is the Honeywell T8600D.

[Woussko]

A very simple test to be sure it really is the thermostat.

Open a window in the room where the thermostat is located and close the door so the rest of the house doesn't get cold. Set the thermostat to 80 and leave it. After about 1/2 to 1 hour are you getting loads of heat in the house? If yes, that would mean that your thermostat either has a bad temperature sensor or an over acting anticipator. Be sure to set it back to a more normal setting and close the window.

I would go for a simple non programmable manual thermostat for a replacement. Think about Murphy's law and that keeping things simple help fight off Murphy. This is if the thermostat does need to be replaced.

Bottom line: For your safety and that of others, please call in a good licensed professional HVAC tech to check over everything and help flush the crud out of the bottom of your boiler. He needs to check and be sure all safety devices are working properly and any that aren't must be fixed or replaced ASAP.

[zuffy]

This isn't so much of a DIY but more of me wanting to find out more info before the pro comes in. I just like to be well informed of the situation.

Woussko, I hope understanded your test right. You want me to open the windows in my living room where the thermostat is located and then close all the doors to the other rooms. If I set the thermostat to 80, wouldn't the boiler stay on because now the living room is cold regardless if the other part of the house is warm? Isn't that how a thermostat works? Am I missing something? Sorry to sound so stupid.

[Woussko]

Zuffy

You really don't need to open the window. The idea is to set the thermostat well above the room temp and be sure the boiler fires up and keeps fired for some time. My idea is to try to be sure one of your safety devices isn't what's shutting the boiler off.

Normally a thermostat will sense the need for heat, close contact(s) and keep them closed for a good 5 minutes if not longer. When the fire starts, the anticipator (intermal part of thermostat) heats up the bi-metal coil or other temp sensor and when heated up some then the circuit opens.

My idea is to rule out that anything but the thermostat is the cause for short cycling there. You could just short out the wires, but I recommend not doing that for now and just set the thermostat high. You could just open a window in the same room it's in. The test is to be sure there is a call for heat for a good 1/2 hour and see how the boiler behaves.

Please note that not all thermostats have anticipators. Some of the new electronic ones don't need them.
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To help save you confusion, maybe this is how I should post this little test.

Just open a window near your thermostat (if you can do so) and also set it up high for the test. Don't worry about closing doors at this time. I was thinking of a way to help hold in heat. Forget that for now.

After about 1/2 hour, close the window and reset the thermostat. Then please let us know what happened. Did your boiler fire and stay fired long enough so the radiators got good and hot or did the boiler fire, shut off soon, fire again and such.

Please go sit near the boiler and observe it, and make notes of what happens. If anything seems to be going wrong, shut it off. Do not chance safety. If your gut tells you something bad is happening, shut off the boiler.
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I would also call a good HVAC tech to come and check things over. There's no reason to put this off. It's great that you want to learn things, but don't risk safety or having a cold house. Call now if you haven't done so. Ask friends and neighbors for recommendations or horror stories about who not to call.

[zuffy]

OK, got it. I will post the result tonight. Thanks Woussko.

I have asked my in-laws to call the HVAC tech they know and used to help them installed 2 boilers and 2 WHs in their house. He is kind of busy so in the meantime, I was just trying to find out as much as possible of my problem.

[zuffy]

OK, here is a log of my testing. I did not open any windows.

7:39pm - manually override the thermostat from 68 to 80 degree. water is clear at the glass tube. psi gauge needle is at the bottom

7:52pm - thermostat is still showing 68 degree. boiler is still firing. glass tube is water is light brown

7:59pm - boiler stop firing. thermostat still calling for heat with the flame icon. psi is close to the third mark so I will assume it's 2.5 - 3 psi

8:00pm - boiler is back on. thermostat is now showing 69 degree. psi gauge is back to the bottom

8:02pm - psi needle is at the second mark, assuming 2 psi

8:03pm - boiler stop firing. thermostat still calling for heat with the flame icon. thermostat showing 69 degree. psi is at the third mark, assuming 3 psi

8:04pm - boiler is back on. psi gauge needle is at the bottom

8:05pm - psi needle is at the second mark, assuming 2 psi

8:07pm - boiler stop firing. thermostat still calling for heat with the flame icon. thermostat showing 69 degree. psi is at the third mark, assuming 3 psi

8:08pm - I lowered the thermostat back to 68 degree to stop the testing

Looking at the gauge, is the second mark consider 2 psi?

http://mysite.verizon.net/zuffy/psi.jpg

[NHMaster3015]

This is the third time, but I'm gonna say it again. Change the thermostat. Refer back to my original post if you want. Be sure to read the very beginning. Change the thermostat.

[HVAC HAWK]

i dont do service work i install boilers so i'm not up on all the trouble shooting .i think you have a good idea about things now and i'd say call some one to look at it ,it will be safer that way .
it is hard to help when we dont have hands on but people here try and some times it works and some times it does not .

sorry i cant come up with some more ideas .

[zuffy]

I think I have done all I can thanks to everyone's suggestion. As I stated before, I'm not trying to save a few bucks as a DIY'er. I just want to troubleshoot a bit so I have a clearer idea of the problem(s) so when the pro comes over, I can explain the problem(s) in more details. I'm in the IT support field, so troubleshooting is in my blood. :D

[Ruudacguy]

That T8600D has some goofy quirks about it. Listen to NHMaster and pitch it. But if you want to verify that the stat is the problem: 1) turn off the power to the boiler 2) disconnect both wires from the stat and tie them together 3) turn the power back on and time it just like you did before.

[Woussko]

With that info, I agree about changing the thermostat and I really don't see the need for anything fancy. If someone will be at home all the time you'll most likely want a pretty much fixed constant temperature. It might be an idea to lower it a little at night but there's nothing nice about waking up to a cold house.

Now please get a good tech to come by and give everything a careful checking over. Do replace the thermostat and keep it simple. There's nothing more angering than having it too hot or cold and not being able to change the settings of some darn Yaupo Schight fancy thermostat. With a simple manual type You and not It are in control. The fancy programmable ones are only worth it if you are away for a long time during the day and just can't bother to lower it some on the way out the door.

There are far better and more effective ways to save energy.

Ruddacguy has the idea about the thermostat test. You could try it and make note of the current connections. When reinstalling the thermostat or installing a new one, do have a small level handy. They need to be level.

Note to tech:
1) Replace the pressure relief valve and add a proper discharge pipe so it won't blast steam on/at people if it ever does blow. 2) Check limit switch and replace if needed. 3) Check low water shut down switch. Replace as needed.
4) With the boiler shut down and the tech there, be sure to give the boiler a good flush. It would be a good time to totally drain your system, fill it up just a bit and drain the boiler again and again until it comes out clean. Then fill the system and work out air. Do this with the tech there and be sure everything works correctly before he leaves.

A boiler full of mud/rust/sludge will not operate properly and it isn't safe. Get the crud out of it now.
Be 1000% sure the boiler has been shut off and allowed some time to cool before you drain it and/or your system.
Never drain out or fill a boiler that is fired or has just shut off. Never add water to a fired boiler. If it seems to be low, shut it off fast, allow cool down time and then and only then add water.
Never, ever skimp on safety devices. If in doubt replace them.

[Ruudacguy]

Before I put the 2 Mods in my house, I had a 120k single stage controlled by a T8600D. Whenever coming out of setback from 64 to 70, the furnace would cycle at about 68 degrees. I finally figured out that stat did that on purpose to prevent overshooting the setpoint. There may have been a way to turn that feature off, or adjust it, I dont remember. I suspect this feature may be partially malfunctioning on your stat.

[DuckButter]

I'm in the IT support field, so troubleshooting is in my blood. :D

It occurs to me that it might be a syntax error in the flame roll out.

Couldn't resist.
Ruudac just suggested a great idea...a better version of Wousko's thermostat idea.
Tie the two thermostat wires together from the boiler and see if it continues to short cycle while running.
When you connect the two wires, you close the circuit like a thermostat does when it calls for heat.

And, NHMasters gonna blow a gasket..at least let the guy know you're not ignoring him!

[zuffy]

I'm not trying to ignore NHMaster. :lol: I heard him loud and clear.

I went to a vocational high school and took up electrical. Definitely top 5 student so I have a good understanding of electrical.

If I am replacing the thermostat, it will be a fancy programmable one.
1) I love gadget
2) Like the 7 day programmable vs the 5-1-1 or 5-2. Even though I leave the house at a constant temperature 24/7, I do adjust base on outside temperature
3) I don't expect my grandmom to be at the house for too long so I like to have the programmable option for future usage

[Woussko]

Zuffy

Please don't be another Yaupo Schight with trouble making toys. For now PLEASE just get a simple basic thermostat your grandma can deal with. Once she is gone (sad times for sure) then you can buy the new micro processor model with loads of memory so you can set the temp hour by hour over a full month just as you like. It can have an outdoor temp and humidity sensor and even be able to sense when you're in bed sawing away or when no one is home. It will be equipped to flash a bright strobe if the temp inside runs below or above set limits. That way your neighbor will phone you that something is wrong. They really do have such models if you want to pay big $$$ and deal with programing the damn thing.

I like to follow the old K I S S rule and keep Murphy under control.

Give Rudd's test a try and please report what happens. Something is wrong where the boiler shut down only to restart after just a few minutes.

The best thing you can do is get a good tech over, let him be alone with things and for him to check it totally out. Also get the sludge out of the bottom of the boiler. My bet is the whole system needs a good flushing but that's something for warmer weather rather than now.

[NHMaster3015]

You know what. I still bet it's the thermostat, but looking at the picture I may have over looked something. Rare but possible. The boiler has an electronic damper on the flue. The boiler will not fire with the damper closed. There is a micro switch that allows the circut to close and fire the burner. If the damper, motor, or switch are F'd up, I have seen this also cause short cycling. Not common, very rare, but possible. To check. Pull both wires off the switch and bug them (tech. term) together. Manually open damper. See if it makes a difference.

[zuffy]

I am off today so here is another test log.

approx 10:25am - set thermostat from 68 to 69. boiler is firing

approx 10:35am - boiler stop firing. psi 3. thermostat still calling for heat

approx 10:36am - boiler fire back on. psi 0

approx 10:39am - boiler stop firing. psi 3. thermostat still calling for heat

approx 10:40am - boiler fire back on. psi 0

approx 10:43am - boiler stop firing. psi 3. thermostat stop calling for heat

approx 10:55am - took the thermostat off and checked the voltage from the 2 wires connected to R and W. Measured at 21.7V

approx 11:00am - power off boiler and then crossed the 2 wires to close the circuit

11:04am - power on the boiler. boiler is firing. psi 0

11:11am - boiler stop firing. psi 3. I can hear the water boiling inside the boiler

11:12am - boiler fire back on. psi gauge needle is just above the first mark

11:14am - boiler stop firing. psi 3. I can hear the water boiling inside the boiler

As for the damper. When the damper opens, I know the boiler is about to fire up and when the boiler stop firing, I know the damper will close. Doesn't sound like the damper is mulfunctioning.

I was reading the Honeywell thermostat installation manual again. It say to change the cph to 1 for gavity/steam system, which I did from 3 to 1.

Base on yesterday and today's log, it seem like the boiler stop firing once the psi gets to 3, regardless if the thermostat exist or not. Is that a good thing or bad thing?

Time to push my in-laws again to get that guy over to check my system.

[NHMaster3015]

A very good thing indeed. If fact 3psi is a bit high for residential but if it's working don't mess with it.

[zuffy]

Can I assume I don't seem to have a problem anymore? The air vents in the bathroom and master room are not hissing loudy anymore after the cleaning. Since changing the cph from the default 6 to 3 and then to 1 which is the correct setting for my steam system, the boiler have not been short cycling. The last time the boiler came on around 11:12am, it just came on at 3:23pm and stop at 3:43pm. The thermostat did not call for more heat.

[Ruudacguy]

You should not get a voltage reading across R and W. Its the same side of the 24 volt circuit. R, comes from the transformer to the stat, and W goes back to the gas valve but may go through a limit or 2 first. This would be like pulling a SPST light switch off the wall and measuring 120 volts between the 2 wires. Something is weird there.

[zuffy]

It's only a 2 wires system for heat only. That is how it's connected in the thermostat. If those 2 wires touch to close the circuit, why shouldn't there be voltage. Am I missing something?

[NHMaster3015]

There should be around 24V at the thermostat.

[Ruudacguy]

Checking the voltage across R and W at the stat is absolutely worthless. Depending on the gas valve and what type of safeties the system has, you might get a reading of zero, or a small voltage reading. Doing this, you are measuring between R, and C including the resistance of the entire gas valve circuit and any inline low voltage safeties. Checking the voltage between R and a good ground WILL tell you something worthwhile. This will tell you what the actual transformer voltage is. On most residential systems you will see around 27 volts. On residential systems installed in commercial buildings with 3 phase power I usually see around 21. On 3 phase commercial systems with multi-tap transformers I usually see around 30.

[Masterplumb]

If all that stuff checks out, go to the part in my post about cleaning the pig tail.

If it were the pigtail, the system would NOT be shutting off, it would keep on running most likely until the relief valve blew.

[Masterplumb]

Steam systems run best at a max of 2psi.
I noticed in the pics that the guage was at or near zero, was it operating at the time?
Also I noticed the pressuretrol was all the way down to .5, maybe a little increase might slow the frequency it cycles..don't go more than 2 psi, in fact only a small amount per try until it either stops short cycling or you're @ 2psi on the boiler guage when it shuts off.

My #1 guess is whats already been mentioned, the pigtail feed to the pressuretrol might be clogged, thats very common.
Usually it's good measure to replace both pigtail and presuretrol at the same time while you're at it.

IF any of this sounds confusing, please consider getting a pro to look at it, if you mistake one thing for another and accidently alter/damage a safety, you could create a hazardous situation.

The Honeywell control was never touched. It has always been at the same level. There is line that says 2 and below is .5, the indicator is in between.

If the Honeywell thing is the pressuretrol, I will get a pro to replace it if he agree that is the problem. I know better than to try to fix something I'm not comfortable doing.

Thanks for the help.

The pressuretrol is NOT the problem, Its an air problem, the AIR vents are not working properly. If the air cant escape the steam cant get in. Replace the main air vents and the radiator air vents.

[NHMaster3015]

You need to go back thorugh the posts, It was the thermostat all along. Exactly what the first part of my original post said.

[DuckButter]

The pressuretrol is NOT the problem, Its an air problem, the AIR vents are not working properly. If the air cant escape the steam cant get in. Replace the main air vents and the radiator air vents.
True, he mentioned after the fact that the boiler had been working fine at the same setting before, if it were a ceased pressuretrol, or clogged pigtail, the boiler wouldn't start at all.
You're right, if the pressuretrol were short cycling the boiler it would be a venting issue (I'd been semi-guessing the setting had been tampered with).
In the real world, we'd probably jump the tt connections, or pressuretrol to conclude this.
I'm pretty sure he'd mentioned the vents were working, like NH said:
You need to go back thorugh the posts, It was the thermostat all along. Exactly what the first part of my original post said.
...but I'm not up to reading back.
I think NH got it, but we don't get the luxury of jumping the connections to find out for sure.

[zuffy]

You need to go back thorugh the posts, It was the thermostat all along. Exactly what the first part of my original post said.

Actually, it's not the thermostat. I think it was the default CPH set at 6. Since changing it to 1 CPH, it's not short cycling anymore. BTW, I did replace the thermostat with a Honeywell VisionPro TH8110. With the CPH at 1, it's functioning the same as with the old thermostat.

[zuffy]

The pressuretrol is NOT the problem, Its an air problem, the AIR vents are not working properly. If the air cant escape the steam cant get in. Replace the main air vents and the radiator air vents.

Just curious, where can I find the main air vents and do they look like the ones found in the radiators?

[Masterplumb]

Just curious, where can I find the main air vents and do they look like the ones found in the radiators?

The main vents are usually at the end of the main(s) right before they drop down into a return.

[Masterplumb]

True, he mentioned after the fact that the boiler had been working fine at the same setting before, if it were a ceased pressuretrol, or clogged pigtail, the boiler wouldn't start at all.
You're right, if the pressuretrol were short cycling the boiler it would be a venting issue (I'd been semi-guessing the setting had been tampered with).
In the real world, we'd probably jump the tt connections, or pressuretrol to conclude this.
I'm pretty sure he'd mentioned the vents were working, like NH said:

...but I'm not up to reading back.
I think NH got it, but we don't get the luxury of jumping the connections to find out for sure.

You said if it was a clogged pigtail the boiler wouldnt start? I believe you have it backwards, if the pigtail was clogged the pressure-trol would never get a reading, making the boiler cycle LONGER and build up the steam pressure, most likely until the relief valve blew.

The thermostat is hardly ever an issue with cycling, its usually a pressure problem, i.e. the air cant escape from the vents fast enough and this will make the pressure rise faster then normal.

If the rad. vents work but the main vent(s) dont, it takes way too long to vent the system. A usual sign of this is a very audible hissing coming from the radiator vents.

[zuffy]

The main vents are usually at the end of the main(s) right before they drop down into a return.

Can you please translate that into normal conversation language? :lol: I don't understand the plumbing terminology. Got a pic of how a normal main vent looks like?

[Masterplumb]

Can you please translate that into normal conversation language? :lol: I don't understand the plumbing terminology. Got a pic of how a normal main vent looks like?

Coming from the top of your boiler you have either one or two pies coming out. They combine into one common pipe. This pipe will usually run along each side of the basement or directly down the middle, in either scenario at the furthest end of these pipes you will usually see these pipes turn down towards the floor(or just trace the pipes until they go from horizontal to vertical). You will usually see the main air vent(s) before the pipes head toward the floor. I hope I explained myself better! ;)

[HVAC HAWK]

i never seen a air vent at the end of a main there should be a end of the main trap before it changes back to water .
not saying there should not be one just never seen one

[Masterplumb]

i never seen a air vent at the end of a main there should be a end of the main trap before it changes back to water .
not saying there should not be one just never seen one

On a most if not all ONE pipe steam systems you will NOT see an F & T trap or any other "crossover" trap. You do need them on 2 pipe systems

[HVAC HAWK]

On a most if not all ONE pipe steam systems you will NOT see an F & T trap or any other "crossover" trap. You do need them on 2 pipe systems

ok i dont run into one pipe systems thanks

[zuffy]

Coming from the top of your boiler you have either one or two pies coming out. They combine into one common pipe. This pipe will usually run along each side of the basement or directly down the middle, in either scenario at the furthest end of these pipes you will usually see these pipes turn down towards the floor(or just trace the pipes until they go from horizontal to vertical). You will usually see the main air vent(s) before the pipes head toward the floor. I hope I explained myself better! ;)

I traced the big pipe to the other end of my house in the basement. Before it curve to the side of the house (U-turn), there are 3 vertical pipes to the first and second floor radiators I guess. Then, it curve again and there is a tip. I can't tell if that is the air vent you are talking about. Otherwise, I don't see anything else that looks like an air vent.

http://mysite.verizon.net/zuffy/Steampipe1.jpg

http://mysite.verizon.net/zuffy/Steampipe2.jpg

[Masterplumb]

It looks like someone capped off where the main vent should go. Where does that pipe continue to? Does it go back to the boiler?

[zuffy]

The pipe in the second pic goes thru the bathroom wall but I don't see it from the outside. So, I'm not sure if it went up or down and if that is the pipe that return to the boiler.

[DuckButter]

You said if it was a clogged pigtail the boiler wouldnt start? I believe you have it backwards, if the pigtail was clogged the pressure-trol would never get a reading, making the boiler cycle LONGER and build up the steam pressure, most likely until the relief valve blew.

yeah yeah yeah...the other way around.
Who's on first?

Also, referencing F & T trap on two pipe systems...I'm guessing you mean Hartford loop..(?)

[NHMaster3015]

Can I assume I don't seem to have a problem anymore? The air vents in the bathroom and master room are not hissing loudy anymore after the cleaning. Since changing the cph from the default 6 to 3 and then to 1 which is the correct setting for my steam system, the boiler have not been short cycling. The last time the boiler came on around 11:12am, it just came on at 3:23pm and stop at 3:43pm. The thermostat did not call for more heat.

Sorry, I'm a bit confused. Did this post say the problem was solved.?

If not, the discussion of main vents. If you have a one pipe system there, you may not have main vents, the radiator vents serving that purpose.

[NHMaster3015]

[
The thermostat is hardly ever an issue with cycling, its usually a pressure problem, i.e. the air cant escape from the vents fast enough and this will make the pressure rise faster then normal.

www.heatinghelp.com (http://www.heatinghelp.com)

This is right out of Dan Holohans book. Note the very first paragraph.


Steam Problems?

You are now reading a part of Dan Holohan's book, A Pocketful of Steam Problems (with solutions!) You can order the full text from Books & More. That way, you'll have HeatingHelp when you're on that next problem job!

THE BURNER SHORT-CYCLES.

The thermostat is out of calibration.If it is, the burner will be bouncing on and off. Make sure you use an ammeter when you're checking the calibration. Don't guess at that anticipator's setting.
Check, too, to see if the thermostat has a mercury switch. If it does, make sure the thermostat hangs level on the wall. And check to see if the thermostat is in a cold draft, or if it's hanging on a poorly insulated, outside wall. Make the necessary corrections.

The boiler is oversized.You're supposed to size the boiler and fire the burner to the connected piping-and-radiation load. In the boiler manufacturer's literature, they call this load the D.O.E. Heating Capacity. If your boiler is too big, its ability to produce steam will exceed the system's ability to condense steam. The burner will short-cycle.
You may be able to solve the problem by down-firing the burner, but be careful when you try this. You may down-fire to a point where the flue gases begin to condense. Fire only to the connected load.

The boiler is properly sized, but overfired.If there's too much fire, you'll get lots of steam in a hurry. That will quickly raise the boiler pressure and short-cycle the burner off the pressuretrol.
Raising the pressuretrol setting isn't a good solution to this problem. Over-firing will also throw water up into the piping. This leads to water hammer, uneven heating and short-cycling.
Check your gas pressure, or your nozzle size (on an oil-fired system).

The boiler is making wet steam.Check the near-boiler piping against the manufacturer's specifications. If the piping can't separate the water from the steam, the water will cause the steam to condense, and the burner will short-cycle.
Check the boiler water's pH and its cleanliness too. You may have to clean the boiler and the system and balance the pH with chemicals.

The steam traps aren't working.Two-pipe steam is like a ladder. Each radiator is a rung on that "ladder," and at the end of each rung you'll find a steam trap. Part of the trap's job is to keep steam from entering the no-pressure side of the ladder. If even one trap fails in the open position, steam will jump across and pressurize the air on the other side of the system. As the pressure builds, the burner will short-cycle on the pressuretrol.
Float & thermostatic and bucket traps serve the same purpose at the ends of the mains, and at the base of risers. If they fail in the open position, or, with bucket traps, if they lose their prime water, steam can move into dry return lines and cause burner short-cycling and water hammer.
Trap maintenance is essential.

The air vents aren't working.If they're not, the system will trap air and pressurize it. Remember, steam and air are both gases, but steam is lighter than air, so the two won't mix.
When the steam heads down a pipe, it pushes air ahead of itself. If the air can't get out at the end of the pipe (through a vent), the steam will just compress it. The pressure builds, and the burner shuts off on the pressuretrol. The burner short-cycles, but that's not your only problem. The building also remains cold because the radiators and mains are filled with air instead of steam. Usually, someone comes along and raises the pressure. They mean well; they're trying to solve the short-cycling and give the folks some heat. But the higher steam pressure just compresses the air a bit more. It usually doesn't help the lack-of-heat problem. It just raises the fuel bill.
Check the air vents, and clean or replace them where necessary.

The pressuretrol or the pigtail is clogged.If there's sludge in the pressuretrol or the pigtail that connects the pressuretrol to the boiler, the burner will short-cycle. The pigtail's job is to fill with water and keep the steam temperature from reaching into the pressuretrol. A pigtail is a natural collector of sludge. If you can't clean the pigtail (a tough job), replace it.
The pressuretrol has a mercury switch and it isn't level.Some pressuretrols have mercury switches. If the pressuretrol isn't plumb and level, the mercury might trip too soon. That can cause the burner to short-cycle.
If the pressuretrol sits on a pigtail, make sure the curved part of the pigtail faces front to back (when you're looking straight at the pressuretrol). If you have the curved part turned from side to side (so you can see through the circle when you're looking straight at the pressuretrol), the burner might short-cycle. This is because the curved part of the pigtail straightens a bit when heated. As it straightens, the pigtail tips the mercury and stops the burner. When you turn the pigtail so that it faces front to back, it tips the pressuretrol from front to back, but not from side to side. This doesn't affect the mercury switch.

[Masterplumb]

yeah yeah yeah...the other way around.
Who's on first?

Also, referencing F & T trap on two pipe systems...I'm guessing you mean Hartford loop..(?)


No, I mean a float & thermostatic trap. Here is a link to one

http://www.boydeng.com/TrapSizing.htm

[Masterplumb]

[quote=NHMaster3015;131376][
The thermostat is hardly ever an issue with cycling, its usually a pressure problem, i.e. the air cant escape from the vents fast enough and this will make the pressure rise faster then normal.

www.heatinghelp.com (http://www.heatinghelp.com)

This is right out of Dan Holohans book. Note the very first paragraph.



EDIT* Note my use of the words "HARDLY EVER"


Yes, I have been to many of Dan's seminars and have all of his books as well. I understand a t-stat out of calibration can cause cycling issues, but I can tell you that I service alot of residential steam systems and in all my years of doing it, I have yet to come across a t-stat whos anticipator was causing the boiler to short cycle.

The O.P. said he fixed this problem by adjusting his cph to 1, I guarantee this is just a temporary fix.

[Masterplumb]

Sorry, I'm a bit confused. Did this post say the problem was solved.?

If not, the discussion of main vents. If you have a one pipe system there, you may not have main vents, the radiator vents serving that purpose.


Radiator vents are not to be used as "main" vents. All 1 pipe steam systems should have some kind of main vent. Main vents are made to vent the mains and rad vents vent the riser, they are not made to be vents for the whole system.

[NHMaster3015]

This has been a tough one because I'm not really sure what he has there. The pictures are good, but not conclusive enough. I have no doubt that he should replace most if not all of the radiator vents. People seem to think that they are a lifetime thing and you and I both know they ain't. Did he say he had F&T's in the house.? I can't remember, but if so these are very often the cause of a multitude of problems and most likely are in need or service. Is the system single pipe or two pipe.? Again I can't tell and I dont think he knows either. Two pipe, wet return systems are prone to blockage of the wet leg if it's below (and I've see above ones also) the boiler water level. When I approach these jobs I usually try to find out what changes have been recently made. Most of these old systems worked very well untill someone decided to mess with the piping and controls. And as you know, making a boiler change, soley based on btu\hr output can cause huge problems because the new low mass boiler make steam much much faster than the old pig they took out. Dropping the pressure can and often does take care of this problem, but you have got to make sure the radiators are all heating evenly. This can take some time. Anytime we do a steam change we replace all the vents because banging around on the old piping dislodges rust and crap and it all ends up in the vents.
I jumped on the thermostat because it was something that he had changed and these new didgital thermostats can cause problems with control systems if not properly calibrated.

[Masterplumb]

I agree there is a gray area from the pictures and description. It is a one pipe system (he said he has air vents on the radiator).

[zuffy]

OK, just to make it more clear on my system. I will try to summarize what I have and the problem(s) in chronological order:

- It's a Weil-McLain EG-40 or 45 gas steam boiler

- 1 pipe system

- Honeywell CT3650 thermostat (not the T8600D as I originally thought, same family though)

- 2 wires to the thermostat, R & W. Heat only

- Bought the house in August. Turn on the heat around late Oct or early Nov.

- Don't remember if the boiler ever short cycle. Just know heat from the radiators was coming out more consistent

- Bathroom and master bedroom air vents would hiss loudly

- Master bedroom has a big water hammer noise a few minutes after the radiator gets heat

- Drained the boiler around mid Nov on a warm day. Drained until gauge glass water looked clean and clean water was coming out

- Took air vents out and clean them. Saw some improvement in the bathroom and master bedroom but water hammer still exist in master bedroom

- Changed CPH from default 6 to 3. This stopped the short-cycling somewhat. Eventually, I changed it to CPH 1 since that is the setting recommended in the Honeywell manual for a gravity steam system

- Pigtail is checked, not clogged

- Pressuretrol indicator is set between 2 and .5

- With thermostat or without thermostat by crossing the 2 wires, the boiler would turn on for approx. 20 minutes and stop once the it reach PSI 3. It will stop for approx. 1 minute for the PSI to reset back down to 0. Then fire back up for approx. 3 minutes before the it reaches 3 PSI again. This will repeat for a few more time before it reaches the set temperature in the thermostat

- Heat have always been even at all the radiators

- Replaced thermostat with a Honeywell VisionPro TH8110. Set CPH to 1. Yes, it is level

- Drained the boiler because I can see medium brown water at the gauge glass. Clean water at the guage glass and drain but once the boiler fires back on, I see brown water again.

- Replaced master bedroom air vent with the same brand and model. Also, the third bedroom air vent is replaced because it looks old and the vent was painted a bit. I replaced it with a bigger air vent. Now, I don't hear any or very minimum hissing from the bathroom, master bedroom, or the second bedroom. The third bedroom is hissing like crazy with the new air vent. Maybe I will try to put the old one back and see what happen.

- Water hammer still exist in the master bedroom after replacing the air vent in the master bedroom

- Don't see any air vent at the end of the main pipe

The O.P. said he fixed this problem by adjusting his cph to 1, I guarantee this is just a temporary fix.
So you think this is only temporary?

[Masterplumb]

Bathroom and master bedroom air vents would hiss loudly

This is due to the fact you need to add/replace main vent

- Master bedroom has a big water hammer noise a few minutes after the radiator gets heat

You need to check the pitch of the radiator, it needs to be piched towards the radiator valve.

- Took air vents out and clean them. Saw some improvement in the bathroom and master bedroom but water hammer still exist in master bedroom

You cant/shouldnt "clean" air vents. Replace them with the proper size orifice

- Changed CPH from default 6 to 3. This stopped the short-cycling somewhat. Eventually, I changed it to CPH 1 since that is the setting recommended in the Honeywell manual for a gravity steam system

1 cph imho is not enough. Replace the rad vents and install a new main air vent (sized correctly) and put the t-stat back to 3cph

- Pigtail is checked, not clogged

It didnt appear to me it was

- Pressuretrol indicator is set between 2 and .5

The pressuretrol should be set at .5 and the inside wheel should be set for 1 giving you a cut-out at 1.5 psi and it will come back on at 1.0

- With thermostat or without thermostat by crossing the 2 wires, the boiler would turn on for approx. 20 minutes and stop once the it reach PSI 3. It will stop for approx. 1 minute for the PSI to reset back down to 0. Then fire back up for approx. 3 minutes before the it reaches 3 PSI again. This will repeat for a few more time before it reaches the set temperature in the thermostat

3 psi is too high, set the pressuretrol like I stated above

- Heat have always been even at all the radiators

- Replaced thermostat with a Honeywell VisionPro TH8110. Set CPH to 1. Yes, it is level

It should be level but it really doesnt matter on a digital t-stat. Its just cosmetic.

- Drained the boiler because I can see medium brown water at the gauge glass. Clean water at the guage glass and drain but once the boiler fires back on, I see brown water again.

Steam systems can be very dirty. Try and stay on top of it by blowing down once a week.

- Replaced master bedroom air vent with the same brand and model. Also, the third bedroom air vent is replaced because it looks old and the vent was painted a bit. I replaced it with a bigger air vent. Now, I don't hear any or very minimum hissing from the bathroom, master bedroom, or the second bedroom. The third bedroom is hissing like crazy with the new air vent. Maybe I will try to put the old one back and see what happen.

Main vent!

- Water hammer still exist in the master bedroom after replacing the air vent in the master bedroom

Air vents and water hammer in the rad are different issues. See above about pitch.

- Don't see any air vent at the end of the main pipe

You need one at least.


So you think this is only temporary?
Yes I do. Replace vents, add at least one main vent and set tstat back to 3 cph

[zuffy]

Thanks Masterplumb.

The master bedroom radiator look pitched. Maybe I need to elevator it a little more.

I need to doublecheck but the last time I open the pressuretrol, I think the dial wheel was at 1.

As for adding a main vent, is there only 1 type?

Also, 3 cph is a better setting for a steam system?

btw, I noticed your location is NY. Do you cover Brooklyn?

[zuffy]

OK, I did 3 things tonight.

1) Very warm day today so I took this opp to flush the boiler again. I think I flush it more thoroughly this time.

2) I adjusted the pressuretrol to .5. Before it was between 1 and 2. I look inside the pressuretrol wheel, I see the 1 in front but not sure where the indicator mark is to know for sure it's set to 1. But I think it's set to 1 since the pressuretrol was set between 1 and 2 and the boiler would stop when it reaches 3 psi.

3) I checked the master bedroom radiator. It was pitched but I guess the wood that is being used sag somewhat to make the radiator even base on my level indicator. The radiator is about 32" and I elevated it approx .5". Too warm to test the boiler tonight. Will wait for a colder night.

[NHMaster3015]

With thermostat or without thermostat by crossing the 2 wires, the boiler would turn on for approx. 20 minutes and stop once the it reach PSI 3. It will stop for approx. 1 minute for the PSI to reset back down to 0. Then fire back up for approx. 3 minutes before the it reaches 3 PSI again. This will repeat for a few more time before it reaches the set temperature in the thermostat.

Finally we've got somewhere. This here is a classic symptom of a boiler that is over fired. The fact that the radiators heat evenly (even though the M bedroom bangs a bit) means the radiators are indeed venting. (so is the main since if the main was'nt, neither would the radiators.) Changing the cph and or adjusting the pressure trol can slightly decrease the cycling but the main problem here is that the boiler is making steam at a rate faster than the systems ability to direct it. I would give your service Co a call and see if the change the firing rate for you.

[Masterplumb]

Again we disagree but lets say it is over fired, and maybe I'm missing something but how do you properly and safely downfire a gas burner?

[Masterplumb]

Finally we've got somewhere. This here is a classic symptom of a boiler that is over fired. The fact that the radiators heat evenly (even though the M bedroom bangs a bit) means the radiators are indeed venting. (so is the main since if the main was'nt, neither would the radiators.) Changing the cph and or adjusting the pressure trol can slightly decrease the cycling but the main problem here is that the boiler is making steam at a rate faster than the systems ability to direct it. I would give your service Co a call and see if the change the firing rate for you.[/quote]

Here is the o.p.'s first post:

************************************************** *****

I have a Weil-McLain EG gas boiler that provides steam heat. I bought the house last August. Started to turn on the heat probably in late Oct or early Nov. I would leave the thermostat at 68 degree all day because my grandmom is in the house. I don't remember the boiler would ever short cycling like now. It would fire up for 3 minutes every 15-18 minutes but there is no heat to the radiators. If I push the thermostat up 69 or 70, then I can feel the heat is coming out from the radiators. Or if I let the room temperature drop to 66-67 and then set the thermostat to 68, then I can feel the heat coming out from the radiators.


************************************************** *******
Notice in the 1st paragraph he states:

"I dont remember the boiler short cycling like now. It would fire up for 3 minutes every 15-18 minutes but there is no heat to the radiators"

Did the boiler all of a sudden become overfired?
This is the classic symptom of an airbound steam system.

[NHMaster3015]

Well, hell, I don't know. I've pretty much run through all the possibilities in my mind. Air bound seems ok except the radiators do heat up if he cranks the stat up,? I still think replacing the main and rad vents is always a good idea but I'm not sure that's the prob. I shot a mail off to Dan H. If anyone knows it's gonna be him but I fear the info is just too limited. Hell, you're in NY, stop in a give her a look see.. Ha. I think you can down fire the boiler by changing orifice size, but then If I have read this right the boiler will run for 15 to 20 minuts untill she makes steam and then the short cycling starts. That makes me think of three things. Bad pressure switch (rare as hell but possible) Main vents totally plugged (but he say's there are none) Boiler over fired. (can't tell without counting and sizing rads) and finally the LWCO if F'd up. Ok so thats four and just for grins I'll another, boiler is surging badly (but I think he said it is'nt) I'm too lazy to read that far back. Lets just rip the f-ing thing out and convert to FHW.

[zuffy]

I will ask the question again since I don't think I got a clear answer. General speaking in a steam system, if I set the thermostat very high or cross the 2 wires to fire up the boiler, will it stay fire on continueously, no cycle on and off, until it reach its' set point? Is that the normal operation?

[NHMaster3015]

No it's not normal and it leads me to think perhaps the pressuretrol is either set all wrong. I.E. differential is set too close. or the thermostat anticipator is set wrong.

[Masterplumb]

I will ask the question again since I don't think I got a clear answer. General speaking in a steam system, if I set the thermostat very high or cross the 2 wires to fire up the boiler, will it stay fire on continueously, no cycle on and off, until it reach its' set point? Is that the normal operation?


Since you havent got a "clear answer" it may be time to call in a pro this way your system is all set to go next year before the cold weather comes.

Your boiler should run until the t-stat is satisfied, but the burner will cycle as the pressure rises and falls according to the pressuretrol.

[zuffy]

Since you havent got a "clear answer" it may be time to call in a pro this way your system is all set to go next year before the cold weather comes.

Your boiler should run until the t-stat is satisfied, but the burner will cycle as the pressure rises and falls according to the pressuretrol.

Isn't that what my boiler is doing now? If I set the thermostat to 80, the boiler is fire on continueously for 15-20 minutes. Once it hit the 3 psi, it cool off for a minute and fire up again. This process repeat several times until it reaches my thermostat set point of 80.

I have no problem calling a pro to resolve my problem but I don't know of a trusty one. For example, my next door neighbor is a master plumber. Most likely, he's the one that installed this boiler when the previous owner was living here. He replaced my water heater back in Nov/Dec because it was leaking. I asked him about my water hammer issue and he kind of blew me off. Similiar with the WH, seem like he didn't want the job. I wasn't trying to get free work, discount or take away from his work schedule. I was paying him his rate and I would have no problem paying him if he wanted to look into my heating issue. Maybe it's the neighbor thing where he think I will bother him a lot.

[NHMaster3015]

Can I assume I don't seem to have a problem anymore? The air vents in the bathroom and master room are not hissing loudy anymore after the cleaning. Since changing the cph from the default 6 to 3 and then to 1 which is the correct setting for my steam system, the boiler have not been short cycling. The last time the boiler came on around 11:12am, it just came on at 3:23pm and stop at 3:43pm. The thermostat did not call for more heat.

Are you still having the problem or did changing the cph fix it.?

[zuffy]

Are you still having the problem or did changing the cph fix it.?

Since the cph change from 6 to 1, it's not short cycling like in my original post. Before, when the boiler reach the set point temp at the tstat, the boiler then would fire for 3 minutes every 15-18 minutes but no heat at the radiators. Only when I push the temp up at the tstat, then the boiler would fire for longer and get heat at the radiators. This process would repeat until I push the tstat to another high, like someone on drugs, needing more doses to get high.

Now, if I set the thermostat to 80, the boiler would fire on continueously for 15-20 minutes. Once it hit the 3 psi, it cool off for a minute and fire up again. This process repeat several times until it reaches my thermostat set point of 80 because the thermostat was still calling for heat. Obviously, the repeat process is zero or minimum if I am only raising the temp 1-2 degrees. So, really, is this normal?

[plumberscrack]

Where is the thermostat in relation to the nearest radiator?

[zuffy]

The living is approx. 18' x 25' so I would say it's about 23-24' away. Radiator is at the front of the house and there is a small one in the door entrance, about 4' away. There are no radiator at the kitchen.

http://mysite.verizon.net/zuffy/DSC01760.jpg

http://mysite.verizon.net/zuffy/DSC01759.jpg

[Woussko]

If you haven't had a good HVAC tech come by and check it out yet, please just do so. This thread is insane. All anyone can do remotely is to try to make good guesses based on what's posted. A good tech could get more done in an hour or two than what's on this thread of over 80 posts. In addition you have safety issues that need to be checked out and fixed right. Please do yourself and your family the favor of getting this fixed and fixed right. No more "Penny Wise and Dollar Foolish" nonsense. Sooner or later something bad is going to happen. Get a good tech or two to come by and check it over and then advise you. You're not being forced to do as they say and spend huge amounts of money. If more than one says you need the same things fixed, then please just do it. If they disagree then ask questions and maybe get a third in the check it over.

[zuffy]

I am not aware of any safety issue other than the relief value which was resolved long before I started this thread.

There are just too many HVAC techs in NYC to know which one is good. As I stated before, I have a master plumber next door, whom license # is in the low hundreds, that doesn't seem to want to help. Maybe it's neighborphobia. :lol: That is my problem unless someone can refer one.

I still don't understand why someone can tell me a simple yes or no if that is how a normal steam boiler suppose to work. Is it a liability issue?

[NHMaster3015]

I'm gonna go out on a limb here and say that based on your last couple of posts, yes it is operating a near correctly as it can. would I like to see the cycle time longer.? Yes I would, but I suspect there's a bit more boiler there than the piping and radiators can handle. Can you down fire the boiler,? You're gonna have to get a gas tech out there to determine and take care of that issue. I believe it is as simple as changing the orifices in the burners but there is NO WAY a home owner should attempt that.

[NHMaster3015]

If you haven't had a good HVAC tech come by and check it out yet, please just do so. This thread is insane. All anyone can do remotely is to try to make good guesses based on what's posted. A good tech could get more done in an hour or two than what's on this thread of over 80 posts. In addition you have safety issues that need to be checked out and fixed right. Please do yourself and your family the favor of getting this fixed and fixed right. No more "Penny Wise and Dollar Foolish" nonsense. Sooner or later something bad is going to happen. Get a good tech or two to come by and check it over and then advise you. You're not being forced to do as they say and spend huge amounts of money. If more than one says you need the same things fixed, then please just do it. If they disagree then ask questions and maybe get a third in the check it over.

come on wussy. I love these long threads they really hold your attention. Let's go up a couple and fight over flat rate pricing. That one's been going on for months :grin:

[zuffy]

Thank you. And I am not that crazy to attempt that. I know what my limitation is and use common sense.

[DuckButter]

I am not aware of any safety issue other than the relief value which was resolved long before I started this thread.
Exactly, just as simple as a UNIX system...just push buttons and it works on its own.


There are just too many HVAC techs in NYC to know which one is good. As I stated before, I have a master plumber next door, whom license # is in the low hundreds, that doesn't seem to want to help. Maybe it's neighborphobia. :lol: That is my problem unless someone can refer one.
Are you asking him to do it free?
Very common for plumbers to avoid neighbors for this reason.


I still don't understand why someone can tell me a simple yes or no if that is how a normal steam boiler suppose to work. Is it a liability issue?
Lets say that the problem turned out to be an issue with your gas valve not working right...you could have a potential CO problem, explosion waiting, or fire hazard.
Although your sure you've described every nook and crevice in detail, it's just impossible to know that your interpetation is the correct interpretation.

[zuffy]

Exactly, just as simple as a UNIX system...just push buttons and it works on its own.
Nothing is. You are using worst case scenario.

Are you asking him to do it free?
Very common for plumbers to avoid neighbors for this reason.
Absolutely NOT. I know the feeling when friends and family members asking me for computer help. When I asked him to replace my water heater, I didn't ask his rate first, I ask if he wanted the job and then asked the rate.

Lets say that the problem turned out to be an issue with your gas valve not working right...you could have a potential CO problem, explosion waiting, or fire hazard.
Very true but it's getting to the worst case scenario situation. I have a CO sensor about 10' away so if there is a potential CO problem, I would hope the CO sensor would alert me.

Although your sure you've described every nook and crevice in detail, it's just impossible to know that your interpetation is the correct interpretation.
Yes, very possible. Just like I don't expect a common person to know all the correct terminology when explaining a computer problem.

[Masterplumb]

come on wussy. I love these long threads they really hold your attention. Let's go up a couple and fight over flat rate pricing. That one's been going on for months :grin:


OK NH Master Ill take the bait, are you a f.r. or t&m guy. Hopefully a f.r. guy:D

[NHMaster3015]

OK NH Master Ill take the bait, are you a f.r. or t&m guy. Hopefully a f.r. guy:D

I like either as long as I get my money :D

[zuffy]

Got a plumber to come in. He installed a Gorton no. 1 main air vent. Cleaned the burner, flush boiler, checked the pressuretrol, pigtail, low water feeder, damper, flameout safety, and put some steam cleaner stuff in the boiler.

He said the pitch I did for the master bedroom is good. If there is still water hammering, it will be the pipe under the floor. So far, I haven't heard it and it normally happens 7-10 minutes after the heat is on. It has been over 40 minutes already, nothing so far so that is a good sign.

[Masterplumb]

What did he say was the cause of the short cycling?

[zuffy]

I told him about the boiler was short cycling and then I changed the cph in the thermostat. After the service was done he fired up the burner. The burner was running continueously for awhile until it hits 2 psi and then stop to cool and refire again. He said that is normal.

[NHMaster3015]

I told him about the boiler was short cycling and then I changed the cph in the thermostat. After the service was done he fired up the burner. The burner was running continueously for awhile until it hits 2 psi and then stop to cool and refire again. He said that is normal.

And what did I say, way way back at the beginning of this thread.?
I love being right:D

[zuffy]

Other than the pressuretrol set a little higher than .5 but not 2, it was the cph changed that made the difference.

[Ruudacguy]

Iirc, the boiler did the exact same thing with the thermostat jumpered out, as it did with it hooked up.

From what I read:

Got a plumber to come in. He installed a Gorton no. 1 main air vent.

This is the only thing that has changed.

[Masterplumb]

Iirc, the boiler did the exact same thing with the thermostat jumpered out, as it did with it hooked up.

From what I read:



This is the only thing that has changed.

You are exactly right, that is the only thing that changed (Main Vent)

If the OP now puts the cph back to 3 he will now not have the original problem. The problem want the t-stat, as shown when he replaced the stat, it worked the same way until he lowered the cph. If he now puts it back to 3 the problem will not be back.

[zuffy]

Must be lost in translation. The t-stat was original at 6 when I noticed the problem. I changed it to 3 as stated when I started this thread. Later on, I changed it to 1 and did not noticed a difference but I kept it there since that is the suggested setting from the Honeywell installation manual.

With the main air vent installed, it's operating the same since the cph changed at the start of this thread, minus the the burner stopping at psi 2 now instead of psi 3 after the pressuretrol adjustment.

[zuffy]

Forgot to mention. I only crossed the t-stat wires after I started this thread, which was then comparing to the t-stat set at cph 3. If I have never changed the cph from 6 before the thread, then obviously, there would be a difference if I crossed the t-stat wires.