I'm going to daisy chain TWO on demand heaters!!!!!!!!!!!!

[Dairylander]

Just kidding.
But now that I have your attention, I do have a question.
What's the verb that describes the action where one person applies pressure with a wrench that opposes the pressure of another person trying to tighten or loosen something?
You know, the opposing rotational force that keeps the work in place so you don't rip it off the wall or whatever.
One of my subs said it once and I can't remember what it is.

[porschedude]

In the Aerospace Biz, we call it "Backing UP" or "Back Up Wrench".

\

[PLUMBER RICK]

In the Aerospace Biz, we call it "Backing UP" or "Back Up Wrench".

\

i guess us plumbers must be rocket scientist too:killingme:

same here

rick.

now if you want my Albert Einstein answer, "for every action there is an equal and opposite reaction"
:bravo:
so you see, we too can talk rockets:D

[fronty]

waiting on Dunbar and Duckbutter to ask why you can't daisy chain tankless heaters...

[biscuit]

"Daisy Chain two on demand water heaters"

Personally I think it is a great idea.

Let me know how it works out for you:D

[Pipestone Kid]

Dairylander: Where were you when Fronty was asking all his questions?????:D :D

[NHMaster3015]

If the definition of "daisy chain" means out one and in the other..;) Than what's the point.? If you paralell them then you have indeed acheived nirvana, or at least more hot water. Do it all the time in restaurants.

[gear junkie]

waiting on Dunbar and Duckbutter to ask why you can't daisy chain tankless heaters... You can hook multiple tankless up in series. This is how you deal with low volume such as big homes, resturants and similar establishments. Correct me if I'm wrong because I'm going by memory, but tempering valves aren't required with tankless? I don't think they are but not 100%

[DuckButter]

You can hook multiple tankless up in series. This is how you deal with low volume such as big homes, resturants and similar establishments. Correct me if I'm wrong because I'm going by memory, but tempering valves aren't required with tankless? I don't think they are but not 100%

Most tankless's won't heat over 140...a tempering valve might be redundant.
Though it is a good point.

[fronty]

You can hook multiple tankless up in series. This is how you deal with low volume such as big homes, resturants and similar establishments. Correct me if I'm wrong because I'm going by memory, but tempering valves aren't required with tankless? I don't think they are but not 100%

Do you mean in parallel with high volume?

[Bob D.]

Most tankless's won't heat over 140...a tempering valve might be redundant.
Though it is a good point.


You may be right but I don't think the code (ours anyway) has an exception for tankless heaters that would allow not using a tempering valve to protect handsinks and the like.

[fronty]

Just so I'm on the same page with some of you plumbers, are you saying that people actually run tankless in series? Are you sure you do not mean parallel? I'm pretty sure no manufacturer wants 140 degree water going into their system. What water temps are you looking for, and why would you need water that hot? Is there even a manufacturer warranty that would cover such hot inlet temps? Parallel makes sense to me, but I do not find the need to run it in series. I remember I had to stop a guy from trying to setup a gas furnace/ heatpump setup. He was trying to wire it for first stage heatpump and run the gas furnace as auxiliary heat. He kept on arguing with me that it could be done and it is just like using gas instead of electric backup heat. He didn't realize they couldn't be run at the same time. He couldn't comprehend that the head pressure would go through the roof, if the gas furnace was running with the heatpump. This was a standard blow through coil setup. Well, I had to help him install a kit that used the heatpump as 1st stage heat and used the gas furnace as second stage. It would kill the heatpump before using the furnace. This was a tech friend of mine.

[gear junkie]

Do you mean in parallel with high volume?

Just so I'm on the same page with some of you plumbers, are you saying that people actually run tankless in series? Are you sure you do not mean parallel?
Give me a chance to answer. It might be parallel. I could be wrong, no big deal. I took my rinnai class about 3 months ago and forgot some details. Do you feel better now? See how fun it is to post on more than one thread?

[ToUtahNow]

Give me a chance to answer. It might be parallel. I could be wrong, no big deal. I took my rinnai class about 3 months ago and forgot some details. Do you feel better now? See how fun it is to post on more than one thread?

I believe if you look at the Rinnai Web Site they brag about a couple of homes in the 2006 Builders Show which had their heaters installed in series to increase the capacity.

Mark

[gear junkie]

I believe if you look at the Rinnai Web Site they brag about a couple of homes in the 2006 Builders Show which had their heaters installed in series to increase the capacity.

Mark
So maybe I didn't forget as much as I thought.

[fronty]

I believe if you look at the Rinnai Web Site they brag about a couple of homes in the 2006 Builders Show which had their heaters installed in series to increase the capacity.

Mark

That's insane and intriguing at the same time. Do you have a link? I would like to see how that worked out. It would have to be setup up with controls of some sort or the limits would trip on the second unit. You could also have problems with scolding. Here is how I could see it actually working in series. It would only fire the first unit until a certain gpm's were going through the unit, this would be measured by temp rise. If the 1st stage unit was on with full flow and the temp rise wasn't being met, the 2nd unit would kick on heating the water to the proper temperature. This would make sense, but you would have to add additional controls. This is very interesting for some reason. You could also run this same setup (1st and 2nd stage) using a solenoid valve that opened on the second unit hot outlet when temp rise isn't being reached. Plumbing just became a lot more interesting to me. Feed me some knowledge Utah (please).

[gear junkie]

Feed me some knowledge Utah (please).
It's a trap. Step away from the keyboard. Just a joke.:wave:

[gear junkie]

I just looked in my Rinnai installation manual and it shows the heaters piped in parallel.

[ToUtahNow]

Whether the multiple tankless heaters are installed in parallel or series depends on what you are trying to do. However, whenever installing multiple tankless heaters in close proximity you are suppose to tie them into a single control unit which controls all units.

In theory with a tankless heater the higher the GPM flow through the heater the lower the TD. With the second heater you still have the same flow but because your TD is the same but your incoming water is hotter your supply temperature is higher.

Mark

[ToUtahNow]

I just looked in my Rinnai installation manual and it shows the heaters piped in parallel.

Consider on the East coast where you might have a supply at 40 degrees but can only get 65 degree TD out of your tankless what do you do for your dishwasher. At 104 degrees you will have a perfect shower as long as you don't blend the water but what do you do to dissolve the soap in the dishwasher where the soap requires 140 degrees to dissolve?

Mark

BTW: Another neat use for a tankless is in series with a solar system. You eliminate your storage tank and because your supply temp is high you can get away with a smaller electric tankless.

[ToUtahNow]

I just looked in my Rinnai installation manual and it shows the heaters piped in parallel.

Parallel is a much more common installation than series.

Mark

[fronty]

Consider on the East coast where you might have a supply at 40 degrees but can only get 65 degree TD out of your tankless what do you do for your dishwasher. At 104 degrees you will have a perfect shower as long as you don't blend the water but what do you do to dissolve the soap in the dishwasher where the soap requires 140 degrees to dissolve?

Mark

BTW: Another neat use for a tankless is in series with a solar system. You eliminate your storage tank and because your supply temp is high you can get away with a smaller electric tankless.

I was thinking that as well. If the ground water is extremely cold, you could run it in parallel, but I would think every manufacturer has a maximum inlet temp. Right?


EDIT: I MEANT SERIES NOT PARALLEL

[DuckButter]

The reason I think tankless in parallel would be a better idea is the flow restriction feature they come with.
I could imagine a humorous batch of problems with two of them parallel and the flow restriction kicks on with one...the sudden burst of flow cause the next one's restrictor to kick on..and so on.
No doubt thats why you need a CPU to run both in parallel.
In series, I imagine it's a "weakest link" scenario...if a restrictor kicks in on one, the flow is completely slowed for all hot water.

Ben...btw...it's steak...just hadda get that before it got cold.

[ToUtahNow]

I was thinking that as well. If the ground water is extremely cold, you could run it in parallel, but I would think every manufacturer has a maximum inlet temp. Right?

There may be some that do but consider the limits it would put on a circulated system if that were true. I have a project in Laughlin with a 104 degree incoming water which would be perfect for tankless heaters.

Mark

[drtyhands]

Hooked two of the large Rinnias up in parallel with a hundred gallon storage tank and recirc pump.Don't ask me why,thats what the homeowner's smart guy said was the way to go.His wife needs a lot of hot water for her master tub valve after bathing kids.

I remember bringing this up when I was new here.I think I got rebuked for using the wrong terminology.The thread died out shortly after.

I like seeing this one go so much farther.Lots of knowlegeable additions since then:bravo:

[westcoastplumber]

Rinnai states that if you will be installing 2 or more hot water heaters, they must be installed in parallel. Ask any rep or call any tech support for rinnai, and they will tell you the same.

I am sure that the same goes for any other tankless companies also.

[westcoastplumber]

Hooked two of the large Rinnias up in parallel with a hundred gallon storage tank and recirc pump.Don't ask me why,thats what the homeowner's smart guy said was the way to go.His wife needs a lot of hot water for her master tub valve after bathing kids.

I remember bringing this up when I was new here.I think I got rebuked for using the wrong terminology.The thread died out shortly after.

I like seeing this one go so much farther.Lots of knowlegeable additions since then:bravo:

The storage tank seems alittle overkill, but rinnai and many other tankless manufactuers want the recirc loop tied off a storage tank, or even better, and electric water heater,t hey do not want the recirc feeding off the tankless itself, it changes or voids the warrenty.

[fronty]

There may be some that do but consider the limits it would put on a circulated system if that were true. I have a project in Laughlin with a 104 degree incoming water which would be perfect for tankless heaters.

Mark

Yikes, 104 degrees.

[fronty]

Rinnai states that if you will be installing 2 or more hot water heaters, they must be installed in parallel. Ask any rep or call any tech support for rinnai, and they will tell you the same.

I am sure that the same goes for any other tankless companies also.

WC, I know you probably are irritated with me and the other thread, but I need help in ordering isolation valves and a relief valve. Do you think you can help me out? You seem to have extensive knowledge in tankless systems.

[NHMaster3015]

Been a Rinnai dealer and installer for quite a while now. Never heard of series piping them. Always paralell.

[DuckButter]

You may be right but I don't think the code (ours anyway) has an exception for tankless heaters that would allow not using a tempering valve to protect handsinks and the like.

My state doesn't, but I know of one jurisdiction that requires the water heated to 160, then brought down with a tempering valve...in case of legionaires...a bit extreme, but I know where your coming from.

[ToUtahNow]

I saw some spec for tankless heaters which had output temperatures as high as 180 degrees. How I suppose they could have been for space heating or something but without a tempering valve what do you do with 180 degree water?

Mark

[ToUtahNow]

Been a Rinnai dealer and installer for quite a while now. Never heard of series piping them. Always paralell.

I attended a Rinnai seminar last year where they diagramed parallel, series and circulated. I was a little disappointed in the seminar as the engineer spent as much time telling us where tankless won't work so don't over sell them as he did telling us what might work. I'm afraid the technology is still in need of a little work right now but I firmly believe it is the way of the future.

Mark

[westcoastplumber]

I attended a Rinnai seminar last year where they diagramed parallel, series and circulated. I was a little disappointed in the seminar as the engineer spent as much time telling us where tankless won't work so don't over sell them as he did telling us what might work. I'm afraid the technology is still in need of a little work right now but I firmly believe it is the way of the future.

Mark

I went to a 8 hr service class, we cleaned out the shell, and re-installed everything, then diagnosed it, and a total of 8 hrs installation classes.

Parallel install and recirculation off a storage or electric water heater.

Tankless will work, they just need to be installed correctly, proper size GPM, water and gas sizes are a must!!

[ToUtahNow]

I went to a 8 hr service class, we cleaned out the shell, and re-installed everything, then diagnosed it, and a total of 8 hrs installation classes.

Parallel install and recirculation off a storage or electric water heater.

Tankless will work, they just need to be installed correctly, proper size GPM, water and gas sizes are a must!!

No I know they work but the Rinnai guy was real careful to make sure no one told their customer the heaters would do something they couldn't do. Some of the plumbers actually walked out of the seminar swearing to never try a tankless. It seemed real counter productive to me.

Mark

[PLUMBER RICK]

No I know they work but the Rinnai guy was real careful to make sure no one told their customer the heaters would do something they couldn't do. Some of the plumbers actually walked out of the seminar swearing to never try a tankless. It seemed real counter productive to me.

Mark


i had a noritz factory salesman tell me that "tankless are for tree huggers"

as far as parallel or series. the majority of drawings will show parallel.

there is a nice jumper kit designed to tie 2 tankless heaters together. noritz makes them and it alternates the heaters till the next cycle or it turns them both on if the demand is needed.

i've done both parallel and series on tank heaters. i prefer the parallel better.

rick.

[rick1643]

i had a noritz factory salesman tell me that "tankless are for tree huggers"

as far as parallel or series. the majority of drawings will show parallel.

there is a nice jumper kit designed to tie 2 tankless heaters together. noritz makes them and it alternates the heaters till the next cycle or it turns them both on if the demand is needed.

i've done both parallel and series on tank heaters. i prefer the parallel better.

rick.


I like the Noritz, installing two of them next week......The Other Rick

[DuckButter]

I saw some spec for tankless heaters which had output temperatures as high as 180 degrees. How I suppose they could have been for space heating or something but without a tempering valve what do you do with 180 degree water?

Mark
Thats the stdrd operating temp for many boilers.

[ToUtahNow]

Thats the stdrd operating temp for many boilers.

Yes but these are listed as tankless water heaters .

Mark

[plumberscrack]

Yes but these are listed as tankless water heaters .

Mark

A few years ago I installed a Rinnai as a boiler for an addition. Flipping through their website now I don't see the piping diagram I used. In fact, I dont see any space heating diagrams. I wonder if they don't recommend that anymore. Only a couple of models were certified for space heating. There were some special piping requirements. Needed to be primary/secondary setup, high dollar pump for the primary side and strainers.

[Dairylander]

Since most of you seem to have only the installer's perspective on tankless, I'll give just one case from the customer's end.
I had a tankless Takagi installed in my mom's house. My favorite sub recommended them because of how long much longer Asia has been using tankless than we have (I was clueless, I saw wood).
Anyway, a year after install I ordered her utility records from the local gas company. She averaged over $40 savings per month.
Since she paid $1400 for the unit & install, and a tank style would have been around $400, that $1000 difference will be paid for in two years use.
She lives alone in a small house. It seems as though that's where tankless are most beneficial - low use households.
Although, after all I've read from you guys, I'll tell her to bank that extra savings each month into a fund to pay for the service/replacement that she'll need in a few years!

[Aaron91]

The company I work for did this house. I don't remember off hand the model these heaters were, sorry.

http://img88.imageshack.us/img88/8188/pb260017yg7.jpg

[DUNBAR]

I would not of wanted to be the fellow to drill through that wall 5 times.

[PLUMBER RICK]

Since most of you seem to have only the installer's perspective on tankless, I'll give just one case from the customer's end.
I had a tankless Takagi installed in my mom's house. My favorite sub recommended them because of how long much longer Asia has been using tankless than we have (I was clueless, I saw wood).
Anyway, a year after install I ordered her utility records from the local gas company. She averaged over $40 savings per month.
Since she paid $1400 for the unit & install, and a tank style would have been around $400, that $1000 difference will be paid for in two years use.
She lives alone in a small house. It seems as though that's where tankless are most beneficial - low use households.
Although, after all I've read from you guys, I'll tell her to bank that extra savings each month into a fund to pay for the service/replacement that she'll need in a few years!

i have to seriously doubt those figures.

i have stated many times that my non winter gas bill is $15.00 a month. this is for 2 of us with a 18 year old 40 gallon gas water heater, gas dryer and gas, cook top. only standing pilot is the water heater.

so even if i don't use anything else in the house , (dryer, cook top) my savings could only be $15.00 max and that's without using any hot water.

is her water heater strictly for domestic use/ bathing, cleaning? or is it for space heating too?

your gas prices are either sky high or mine are dirt low?

but i do know that a 40 gallon heater out here cost $463.00 just for the heater. plus tax:eek: thanks squamd. (southern calif. air quality management district) new ultra low nox heaters.

a tankless is approx. $1000. cost plus installation (venting, gas line) to replace.

so your $1400 sounds way low and your $40.00 gas savings sounds way high. at least from my perspective.

rick.

[PLUMBER RICK]

The company I work for did this house. I don't remember off hand the model these heaters were, sorry.

http://img88.imageshack.us/img88/8188/pb260017yg7.jpg

arron, interesting that they ran medium pressure gas, but didn't have to vent the gas regulators. also i see a small electric water heater, is that for your circ. line? are all these heaters connected to a common 3/4'' or 1'' cpvc line?

i was under the impression that pex and cpvc needed to be 18'' from the heaters?

is this for both domestic heating and space heating? or do they use a lot of hot water?

rick.

[gear junkie]

A few years ago I installed a Rinnai as a boiler for an addition. Flipping through their website now I don't see the piping diagram I used. In fact, I dont see any space heating diagrams. I wonder if they don't recommend that anymore.
I just took the class recently from Rinnai. If anyone going to DC wants a copy of their installation literature, PM me and I'll bring it up with me.

[ToUtahNow]

I have a friend who is an electrical contractor and recently switched to a small electric tankless. He and his family have had to endure some colder than normal showers but he says he is saving $100 per month on his electric.

Mark

[gear junkie]

also i see a small electric water heater, is that for your circ. line? This should be 6 gal water heater. It's installed so there are no "cold spots" of water. Kinda evens things out a bit. Our instructor said you could use a 2 gal WH but the hot/cold lines aren't the right size so 6 gal is the minimum.
i was under the impression that pex and cpvc needed to be 18'' from the heaters? That's what the code is here but they did do a pretty good job of that cpvc. I disagree with a couple things but it looks good at first glance.

rick.

Ben

[drtyhands]

Look at the two different installers.
The owner of the company who did the show pipe under units.

Then turns it back over to the crooked pipe crew.AAAARRRON:eek::p

Take a good look at your future,PLUMBERS

[westcoastplumber]

arron, interesting that they ran medium pressure gas, but didn't have to vent the gas regulators. also i see a small electric water heater, is that for your circ. line? are all these heaters connected to a common 3/4'' or 1'' cpvc line?

i was under the impression that pex and cpvc needed to be 18'' from the heaters?

is this for both domestic heating and space heating? or do they use a lot of hot water?

rick.


Rick, I see regulators and they do make regulators that don't need to be vented.

Yes, the electric water heater is for the circulation line.

[DuckButter]

I have a friend who is an electrical contractor and recently switched to a small electric tankless. He and his family have had to endure some colder than normal showers but he says he is saving $100 per month on his electric.

Mark
Semi-humorous thought...If you were taking cold showers, you'd use it less too.
What I've learned of the electric tankless's is the only difference in operating cost is the lack of standby heat loss...doing the math on standby heat loss for a 50 gal tank comes to maybe a few bucks a month.
Most electric heaters run in the high 90% efficiency range, tank or tankless, so I'd like to know how he's saving that much?
For giggles, I typed a search for "surface area of a water tank" and found this site...though I'd wager it's outdated, I'd also wager it's not too far off:
Hot Water Heater Tank, Heat Loss Calculation (http://www.leaningpinesoftware.com/hot_water_heater_tank_insul.shtml)

[fronty]

The company I work for did this house. I don't remember off hand the model these heaters were, sorry.

http://img88.imageshack.us/img88/8188/pb260017yg7.jpg


I have a few questions for the pros. It is hard to tell, but it looks like they ran 3/4in cpvc to feed all the units. They then transitioned into 1in cpvc, which is the main hot water line and cold water line inlet. Wouldn't this cause a restriction? It seems like they need high volume for this structure. Wouldn't it have been better to run the 1" line the span of the units? They would then "T" into it and add a reducer bushing before entering each tankless unit. Basically, they would run the 1" line the entire way.

Also, I'm assuming these things are not staged because I do not see any solenoids etc. Is this correct? Would they all be set to come on at the same time?

[fronty]

The west coast crew must still be out drinking.

[HVAC HAWK]

the gas regulators have a pop it in the vent and this does not allow the gas to come out if the regulator blows .

if i was to run the gas line i would have ran one line to the top of the heaters at a higher pressure then put a regulator on that line and run a header with all the branches to the other heaters . i would have ran hard pipe and not yellow pipe ,it looks better .but looking at the other pipes looks don't mater here :eek:

[haycad]

whats the point of that install?im looking at atleast $5000 just for the tanks? and there is obviously enough room for a tank whats the benefit of that system? i dont have alot of knowledge with the tankless?

[ToUtahNow]

whats the point of that install?im looking at atleast $5000 just for the tanks? and there is obviously enough room for a tank whats the benefit of that system? i dont have alot of knowledge with the tankless?

There is about a million BTUs hanging on the wall which represents a lot of fuel. Instead of having a couple of large tanks heating water 24/7 you have tankless heaters which have controllers which fire the heaters on demand and only enough of the heaters to supply the needed demand.

Mark

[Ruudacguy]

the gas regulators have a pop it in the vent and this does not allow the gas to come out if the regulator blows .

Shouldnt the vents off those regulators be piped outside?

[Bob D.]

2494

I downloaded Aaron's photo and squared it up. Things don't look so out of plumb now for the most part. Also, I'm thinking that each of these tankless heaters is dedicated to a specific Bath, Kitchen, or Power room, and their output is not combined to feed to whole house (I believe Aaron said this was a house).

[Ruudacguy]

Sorry guys, there was a whole page worth of posts that I missed.

[HVAC HAWK]

Shouldnt the vents off those regulators be piped outside?

depends on the code we can just have the pop it in for small regulators

[drtyhands]

2494

I downloaded Aaron's photo and squared it up. Things don't look so out of plumb now for the most part. Also, I'm thinking that each of these tankless heaters is dedicated to a specific Bath, Kitchen, or Power room, and their output is not combined to feed to whole house (I believe Aaron said this was a house).

I don't see it.I see combined hot.Yeah,the pipe under the units is straight of course,Look to the left outside the "show" box.

[HVAC HAWK]

2494

I downloaded Aaron's photo and squared it up. Things don't look so out of plumb now for the most part. Also, I'm thinking that each of these tankless heaters is dedicated to a specific Bath, Kitchen, or Power room, and their output is not combined to feed to whole house (I believe Aaron said this was a house).

i think your right about the different rooms because there is 5 pipes not going to a header they are all separate

[drtyhands]

depends on the code we can just have the pop it in for small regulators
Is there anyway to get a model # or picture so I can do some googleing and code research,I'm very interested.

[fronty]

There is about a million BTUs hanging on the wall which represents a lot of fuel. Instead of having a couple of large tanks heating water 24/7 you have tankless heaters which have controllers which fire the heaters on demand and only enough of the heaters to supply the needed demand.

Mark


How do these things control flow? Is there a restriction device in them, such as a solenoid valve. Otherwise, if only one heater fires, it will be mixing with 4 other heaters that did not. This would dissipate a lot of the heat gain into the cold water it is mixing with.

Also, these are 53i which have a minimum gpm flow rate of .5 gallons. Let's say one person is using a large fixture such as a bath tube or shower and that is the only demand for hot water, would this things even fire? If the shower is rated at 2.5 gpms, the units would spread the flow of water amongst them. There would have to be some kind of restricting device. I wonder if Rinnai would approve this type of application.

[fronty]

Is there anyway to get a model # or picture so I can do some googleing and code research,I'm very interested.

It is the 53i, which is a residential unit.

http://www.foreverhotwater.com/model-r53i.php

[drtyhands]

It is the 53i, which is a residential unit.

http://www.foreverhotwater.com/model-r53i.php

Thank-you Fronty,I'll check it out:)

Dude....I was referring to the regulators:confused:

[westcoastplumber]

i think your right about the different rooms because there is 5 pipes not going to a header they are all separate


I think you are talking about the T&P lines. By code, they cannot be piped toghether.

[fronty]

I don't see five pipes going to the same room. I see five pressure relief pipes going outside. If they were running these things for individual fixtures, they should have ran them straight from the outlet of the device to the fixture. They obviously tied them all together in parallel.

[fronty]

I think you are talking about the T&P lines. By code, they cannot be piped toghether.

Good to know. I was wondering if they could have been tied together or not.

[westcoastplumber]

How do these things control flow? Is there a restriction device in them, such as a solenoid valve. Otherwise, if only one heater fires, it will be mixing with 4 other heaters that did not. This would dissipate a lot of the heat gain into the cold water it is mixing with.

Also, these are 53i which have a minimum gpm flow rate of .5 gallons. Let's say one person is using a large fixture such as a bath tube or shower and that is the only demand for hot water, would this things even fire? If the shower is rated at 2.5 gpms, the units would spread the flow of water amongst them. There would have to be some kind of restricting device. I wonder if Rinnai would approve this type of application.


The installation is correct, they have controllers which are programmed to tell the unit when to fire. Correct order would be #1, #2, #3, #4, #5, then the next time, #2,#3,#4,#5,#1, then the next time #3,#4,#5,#1,#2 and so on forever.

They have solenoid valves inside that control flow and have a gradual fire up, so if the unit only needs to use 40,000 btu, only a certain percent of the burner will light up.

The circ is off a electric water heater, so there is no problem there.

the t&p's are all seperate.

[fronty]

The installation is correct, they have controllers which are programmed to tell the unit when to fire. Correct order would be #1, #2, #3, #4, #5, then the next time, #2,#3,#4,#5,#1, then the next time #3,#4,#5,#1,#2 and so on forever.

They have solenoid valves inside that control flow and have a gradual fire up, so if the unit only needs to use 40,000 btu, only a certain percent of the burner will light up.

The circ is off a electric water heater, so there is no problem there.

the t&p's are all seperate.

Oh. Thanks for the info. I couldn't figure out how this thing would operate without a solenoid of some sort. That makes sense now.

[Ruudacguy]

Is there anyway to get a model # or picture so I can do some googleing and code research,I'm very interested.

This is the closest thing I can find.

http://www.maxitrol.com/ventlimiter.html

[HVAC HAWK]

This is the closest thing I can find.

http://www.maxitrol.com/ventlimiter.html

yes that is it

and rob you are right now i see

[westcoastplumber]

I forgot to mention, the post I posted about the firing order of the 5 tankless units, instead of "next time" it is actually based on an 8 hr period.

Weird, I thought it was every 2 or 3 times, but I called the rep to talk about it and it appears to be every 8 hrs

Has anyone else heard this?? Gear, you just took the class, anything you recall?

[drtyhands]

This is the closest thing I can find.

http://www.maxitrol.com/ventlimiter.html
Thanks

[drtyhands]

I forgot to mention, the post I posted about the firing order of the 5 tankless units, instead of "next time" it is actually based on an 8 hr period.

Weird, I thought it was every 2 or 3 times, but I called the rep to talk about it and it appears to be every 8 hrs

Has anyone else heard this?? Gear, you just took the class, anything you recall?
Anything over eight hours requires time and a half.

[westcoastplumber]

Anything over eight hours requires time and a half.


Thanks Adam, you crack me up my friend;) I mean't every 8 hrs of usage, may be not a full 8, but multiple uses, totaling 8 hrs, you dig? or am I confusing the situation??

[Nevada plumber]

When I took my Rinnai certification class, the rep said that the computer would cycle the water heaters so that they would wear evenly. He didn't get more specific then that. Of course, most of the class was telling everyone what the water heaters could not do. It upset some of the people in the class, but to me it made sense. Rinnai has a very good name as far as I know. If they had people selling the products for the wrong situations, it wouldn't be long before they were the Bosch of the tankless water heater world.

[westcoastplumber]

When I took my Rinnai certification class, the rep said that the computer would cycle the water heaters so that they would wear evenly. He didn't get more specific then that. Of course, most of the class was telling everyone what the water heaters could not do. It upset some of the people in the class, but to me it made sense. Rinnai has a very good name as far as I know. If they had people selling the products for the wrong situations, it wouldn't be long before they were the Bosch of the tankless water heater world.


I agree with you Nevada, Rinnai is the best in my book, takagi used to be, but rinnai now has earned their way to the top.

Reps have to tell everyone what they can't do so people stop installing them for the wrong installations. I am tired of everyone saying tankless are crap, because they either cannot or do not or did not install them correctly.

I agree, they have their uses, and not every job is perfect for a tankless, but it is not right to stick all installations in the same catagory.

[DuckButter]

Reps have to tell everyone what they can't do so people stop installing them for the wrong installations. I am tired of everyone saying tankless are crap, because they either cannot or do not or did not install them correctly.

OR...rather than face something new, simply tell customers they suck instead, and convince them to stick with standard tank types.