Water hammer/ expansion tank

[wookie]

Hello,

Incoming city water pressure varys 75-100psi, installed prv set at 60psi. Added t-12 expansion tank at 50 gallon water heater. Set air at 60psi. Ran 3/4" copper for outside hosebib about 30' I used Arrowhead ada 1/4 turn ball valve full port on the new line and replaced the one on the service entrance along with the prv. Did a bunch of other work, adding laundry, utility sink etc. All pipes are secure! When opening the new full port hosebibs front or back I'm getting real bad water hammer. If opened very slow no problem. When I reduced the pressure to 50psi problem lessened but still bad. Removed expansion and plugged, no water hammer problems. Expansion tank needs to stay and I'd like to keep the hosebibs rather than traditional no kink hosebibs. Do I neeed arrestors? Locations? I haven't run into this before. Expansion tank seems ok doesnt get water logged.??? Have a guage at expansion tank and double checked pressures, every thing right on the money.

Thanks , wookie

[Service Guy]

When exactly does the water-hammer happen and for how long?

[wookie]

Only when opening the two new hosebibs for about 2-3 seconds but loud!

thanks wookie

[Service Guy]

Install hammer arrestors on the hose-bibb lines after the ballvalves. It is weird that is goes away when the expnasion tank is removed, I don't think I have seen that before.

[Service Guy]

One more idea to try, bleed out some air in the expansion tank, 60 psi of air is a bit excessive.

[JCsPlumbing]

This doesn't make sense to me. Can anyone answer this and teach me? :o

J.C.

[wookie]

I know, Wasn't feeling to good with the customer standing right there. The hosebibs are ball valves. Installing a arrestor at sevice entrance not easy, no room without complete redo. Thinking about one near the expansion tank and at new hosebib.

Thanks ,wookie

[Killertoiletspider]

Pull the stems on the sill cocks and see if the bibb washer screws are loose.

[Killertoiletspider]

I know, Wasn't feeling to good with the customer standing right there. The hosebibs are ball valves. Installing a arrestor at sevice entrance not easy, no room without complete redo. Thinking about one near the expansion tank and at new hosebib.

Thanks ,wookie

I misread the original post.

Install a conventional hose bibb as opposed to a fast acting valve.

[westcoastplumber]

The full port hose bibb's are acting like a fast closing valve. Are there vacuum breakers on it? take the vacuum breakers off, I had hammer on a hose bibb and I removed the vacuum breaker, it worked perfect, no hammer.

I would also take some of the air out of the expansion tank, try to get some cushion in the system.

Hopefully this helps. good luck and let us know how it turns out ;)

[Service Guy]

I misread the original post.

Install a conventional hose bibb as opposed to a fast acting valve.

I was just about to suggest same thing. I misdread it also, until he re-explained.

[gear junkie]

Many hose bibbs have different threads and won't allow a hose to be screwed on where the vacuum breaker was. Besides not code.

[gear junkie]

Does this happen when the washing machine is running?

[westcoastplumber]

Many hose bibbs have different threads and won't allow a hose to be screwed on where the vacuum breaker was. Besides not code.



This was just to see if it solves the problem, then instead of all the other issues, if it did, he would just replace the vacuum breaker.

Diagnosis only......I guess should have pointed this out ;)

[mrs. westcoast]

Water hammer is a pressure surge or wave resulting when a fluid in motion is forced to stop or change direction suddenly (Momentum Change). Water hammer commonly occurs when a valve is closed suddenly at an end of a pipeline system, and a pressure wave propagates in the pipe.http://upload.wikimedia.org/wikipedia/en/e/e8/Blown_expansion_joint.jpg (http://upload.wikimedia.org/wikipedia/en/e/e8/Blown_expansion_joint.jpg)
These are bellows type expansion joints (http://en.wikipedia.org/wiki/Expansion_joints) taken from a medium-pressure (150-300 psi (http://en.wikipedia.org/wiki/Psi)) steam line. They have been destroyed due to steam-generated water hammer (http://en.wikipedia.org/wiki/Water_hammer), probably in excess of 5000 psi.

[JCsPlumbing]

But why does it operate without any hammer if the expansion tank is removed? :confused:

J.C.

[JCsPlumbing]

And why does it happen when opening the valve?

J.C.

[westcoastplumber]

and now we know what 5000 psi will do to expansion tanks on steam units........thanks honey :wave2:

[Service Guy]

But why does it operate without any hammer if the expansion tank is removed? :confused:

J.C.

I think he has too much air in teh tank, causing some of the excess push...
And why does it happen when opening the valve?

J.C.

...when he opens the valve so quickly.


Its a combination of fast-acting valves and the heavy air-pressure in the expansion tank pushing back.

[JCsPlumbing]

Thanks Carl, that's one of those experience tips that I haven't ran into that will help me troubleshoot in the future.

J.C.

[gear junkie]

I think he has too much air in teh tank, causing some of the excess push...


...when he opens the valve so quickly.


Its a combination of fast-acting valves and the heavy air-pressure in the expansion tank pushing back.I agree with this. Most expansion tanks are preset to 40psi.

[DuckButter]

I think he has too much air in teh tank, causing some of the excess push...


...when he opens the valve so quickly.


Its a combination of fast-acting valves and the heavy air-pressure in the expansion tank pushing back.
My money's on that...bleed out maybe 10-15 psi from the tank & I bet the trouble stops.

[Service Guy]

Thanks Carl, that's one of those experience tips that I haven't ran into that will help me troubleshoot in the future.

J.C.

You're welcome. Troubleshooting is my favroite part of plumbing...its why I do service exclusively. I haven't done any new rough-ins in years. They bore me to death. Give me a weird problem to solve and I am in heaven!

Today had a weird noise vibrating all throughout someone's house. It took me about 2 minutes to find the source....old PRV. Too easy.:cool:

[wookie]

Thanks for all replys! I hate to go to traditional hosebibs after talking up the ones I installed , my customers love em, I'm a hero. According to the installation instructions the air pressure is supposed to to the same as incoming water pressure but I also will take to heart the suggestion of lowering air pressure. Washing machines are not connected yet but I should simulate with the valves installed (Soiux Chief Ox Box w/ arrestors) good point.

Thanks,wookie

[Masterplumb]

Water hammer is a pressure surge or wave resulting when a fluid in motion is forced to stop or change direction suddenly (Momentum Change). Water hammer commonly occurs when a valve is closed suddenly at an end of a pipeline system, and a pressure wave propagates in the pipe.http://upload.wikimedia.org/wikipedia/en/e/e8/Blown_expansion_joint.jpg (http://upload.wikimedia.org/wikipedia/en/e/e8/Blown_expansion_joint.jpg)
These are bellows type expansion joints (http://en.wikipedia.org/wiki/Expansion_joints) taken from a medium-pressure (150-300 psi (http://en.wikipedia.org/wiki/Psi)) steam line. They have been destroyed due to steam-generated water hammer (http://en.wikipedia.org/wiki/Water_hammer), probably in excess of 5000 psi.

Water hammer in a steam system should not be confused with domestic water-water hammer. Water hammer in steam occurs when steam hits condensate and flashes into water. There is a big difference. By the way that is a great example of the force of water hammer....er.....in a steam system

[westcoastplumber]

Water hammer in a steam system should not be confused with domestic water-water hammer. Water hammer in steam occurs when steam hits condensate and flashes into water. There is a big difference. By the way that is a great example of the force of water hammer....er.....in a steam system



Thats the un paid employee for west coast plumbing who posted that picture....and she wonders why she is "un-paid".....





kidding, she is great at marketing and web site design!!!!

[Masterplumb]

Thats the un paid employee for west coast plumbing who posted that picture....and she wonders why she is "un-paid".....





kidding, she is great at marketing and web site design!!!!

I have one of those un-paid workers too. I was thinking of firing her but Id rather not give up half of everything, including my spleen :eek:

[PLUMBER RICK]

any fast acting valve will create a surge. wait till he tries his washing machine and automatic sprinklers.

the ada ball valve hose bibbs are great. i always warn my customers to open slow and close slow.

i give them the same example as when they pull up to a stop light with their car. no putting the pedal to the metal and no slamming on the breaks. they get the idea:rolleyes:

un fortunately putting a vacuum breaker on those hose bibbs really choke down the flow.

there are newer arrowhead hose bibbs with an internal vacuum breaker that flows better and doesn't chatter. it can be identified by its yellow handle. the vac breaker is in the stem assy;)

rick.

[MrsSeatDown]

I have one of those un-paid workers too. I was thinking of firing her but Id rather not give up half of everything, including my spleen :eek:

I think it is ok to go ahead and give up your whole spleen:D Hey it's a bidding tool;)

[wookie]

Well, went back today and as suggested by Service Guy and others I reset the air pressure 5psi lower no change, lowered 10psi and NO water hammer! Before going out I called Amtrol expansion tank tech support and they confirmed that lowering air psi should solve the problem. Still haven't wrapped my head around what happened but problem solved.

If incoming water pressure is 60psi and expansion tank is 60psi there should be no water in tank to surge when opening full port hosebib. I did tap on the expansion tank when in service and it sounded empty to me. I understand that quick closing can result in water hammer??? Opening other valves caused no problems, they're on 1/2" lines just the 3/4" lines.

Again thanks for the help. I don't post much but I'm here reading almost everyday. Just bought a new K-39af and a used Marco w/ 5/8" Gorlitz cable so i'll be asking more ? i'm sure!

wookie

[DuckButter]

Excellent!

[Arts Cabinets]

The problem is vibration caused by the valve only when the water is running and the valve is open in a specific position. Water hammering only occurs at the time a fixture or is turned off.

A vibrating sound occurs as the water is trying to sneak past a soft or loose washer. Arrowhead hose bibbs are famous for vibrating. The problem has nothing to do with strapping the pipes.

Expansion tanks, air in the pipes (if air in a pipe was possible), and air chambers have nothing to do with the noise. The problem can also occur when you have a defective pressure regulator with a soft diaphram or a defective water meter.

How would a cabinet maker know? I used to be a good plumber until I was convinced otherwise.

Remember, this forum is open to the public. Please post all derogatory statements in private messages. Lets keep the forum friendly and professional.

Thank you.

Jack

[DuckButter]

Thank you for your guidance & support Jack, Leonard, Tom, Dick or Harry.
The problem was resolved when he dropped the pressure on the expansion tank...ya gotta read the details buddy!

[Service Guy]

Still haven't wrapped my head around what happened but problem solved.

If incoming water pressure is 60psi and expansion tank is 60psi there should be no water in tank to surge when opening full port hosebib. I did tap on the expansion tank when in service and it sounded empty to me.
wookie

Which is part of the problem. You have a thick rubber balloon expanded in a steel tank under 60 psi of air-pressure. No wonder that the 60 psi of water 'thumps' a bit when it surges through the ball-valve action hose faucets.
Let some of the air pressure out and the balloon will be softer and it will contract against the incoming higher-force water pressure...acting more like a cushion or shock-absorber in the system.

[Arts Cabinets]

Thank you for your guidance & support Jack, Leonard, Tom, Dick or Harry.
The problem was resolved when he dropped the pressure on the expansion tank...ya gotta read the details buddy!

Maybe lowering the pressure masked the problem. Sorry, I'm a slow reader. Maybe I'll catch up on the next round. I'm still learning. 80lb to 90lb is only a little higher than average. The first thing to look at when a noise occurs is the valve, pressure regulator (if any) and the meter. From most posts, is appears that people look at straps, air chambers, and expansion tanks first. Not one of these will cause a pipe, with water flowing, to make a vibration of whistling sound.

Be sweet!

Okay, if my handle is out-of-place, I will make a new and final one.

I love this forum. I love the different ways people think about things. This is useful information. It is good food for thought and I am going to use it to write a book (manual) for my company.

Jack

[DuckButter]

I'd just be happy to have ONE name to call ya, my guess is Jack...wondering where Leonard came from.

[gear junkie]

Maybe lowering the pressure masked the problem. Sorry, I'm a slow reader. Maybe I'll catch up on the next round. I'm still learning. 80lb to 90lb is only a little higher than average. The first thing to look at when a noise occurs is the valve, pressure regulator (if any) and the meter. From most posts, is appears that people look at straps, air chambers, and expansion tanks first. Not one of these will cause a pipe, with water flowing, to make a vibration of whistling sound.

Be sweet!

Okay, if my handle is out-of-place, I will make a new and final one.

I love this forum. I love the different ways people think about things. This is useful information. It is good food for thought and I am going to use it to write a book (manual) for my company.

Jack40psi is the norm and 80 psi is max for watts expansion tanks.

[JCsPlumbing]

The problem is vibration caused by the valve only when the water is running and the valve is open in a specific position. Water hammering only occurs at the time a fixture or is turned off.

A vibrating sound occurs as the water is trying to sneak past a soft or loose washer. Arrowhead hose bibbs are famous for vibrating. The problem has nothing to do with strapping the pipes.

Expansion tanks, air in the pipes (if air in a pipe was possible), and air chambers have nothing to do with the noise. The problem can also occur when you have a defective pressure regulator with a soft diaphram or a defective water meter.

How would a cabinet maker know? I used to be a good plumber until I was convinced otherwise.

Remember, this forum is open to the public. Please post all derogatory statements in private messages. Lets keep the forum friendly and professional.

Thank you.

Jack

So BESTLINE PLUMBING, you apparently were incorrect with your diagnosis & repair. Can happen to any of us.

I have an ethics question for you or anyone. Based on your experience and diagnosis you would have repaired/replaced the hosebibbs, PRV, and addressed the meter in some way. 2 hours labor? That's $600.00 plus materials if I recall correctly. If this doesn't correct the problem, do you refund any of this or do you charge another $300.00 plus materials for the expansion tank adjustment? That's roughly $1000.00 to let the air out of a can isn't it? And for me, I don't always buy the idea of that a plumber "improved" the system justifying cost. I've seen older-superior parts replaced with newer-inferior parts.

Some say you're prices are high but maybe they don't have a clue what it cost to run your type of business. So will make the price lower.

Let's say someone only charged $10.00/hr. Who pays for the plumbers misdiagnosis'?

J.C.

[Arts Cabinets]

So BESTLINE PLUMBING, you apparently were incorrect with your diagnosis & repair. Can happen to any of us.

I have an ethics question for you or anyone. Based on your experience and diagnosis you would have repaired/replaced the hosebibbs, PRV, and addressed the meter in some way. 2 hours labor? That's $600.00 plus materials if I recall correctly. If this doesn't correct the problem, do you refund any of this or do you charge another $300.00 plus materials for the expansion tank adjustment? That's roughly $1000.00 to let the air out of a can isn't it? And for me, I don't always buy the idea of that a plumber "improved" the system justifying cost. I've seen older-superior parts replaced with newer-inferior parts.

Some say you're prices are high but maybe they don't have a clue what it cost to run your type of business. So will make the price lower.

Let's say someone only charged $10.00/hr. Who pays for the plumbers misdiagnosis'?

J.C.

From Jack:
My $280 to $340 per hours is the benchmark I use for contracts like the recent drain job thread. Even though, almost every member balked at my price, it appears that since every member said $1600 for the drain job or higher, almost everyone is charging $300 per hour I totally disagree with the $1600 price because the job, with inspections, etc. is really a two day job or a minimum of 12 hours. You have to figure getting materials, travel, and time to go home or to the office to take a shower when you could be on another job. I would not have charged a penny less than $2800 and I press the customer to do the right thing and replace the entire drainage system for a minimum of $5400. My prices are on my web site.

I mentioned before that I charge different prices for different jobs. On this vibration problem, I would have charged only $65 and would probably have spent less than 15 minutes on the job. All my prices are on my web site. The strange thing about my prices are that I always charge a little less than my advertised prices and when I quote a price on the phone I always quote my higher price and rerduce the price when I arrive. I do the opposite of what you would expect. the average pressure where I live is 60lb to 80lb. I won't consider a regulator until the pressure is over 80 - 85lb. Pressure regulators cause water hammering and hissing sounds.

There is more psychology to pricing that business. Yesterday, I signed a contract to replace drains for $5400. The customer went under the house and had lights set up before I arrived so he knew what his problems were before I arrived. The customer said the price was lower than he expected.

There is a lot to be learned about perceived value. I used to think perceived value was deceived value. It goes far beyond just making your company look good or trying to majke a job look larger and better. There is a method to learn to build your perceived value so that your customers will not want to do business with any other plumber. The best customers you can have want the best job. The thrifty customers always seem to be problem customers before or after the job is finished.

City Girl (Victorina) is back so I have to get back to work. We will be at Whiskey Petes on the California state line on the weekend of the 25th. I love this place because there is gambling, amusements rides, swimming pool, and we will be riding ATV's, shooting rifles, and blowing things up in the desert. We aill have about four children ages 8 to 13 and anyone is welcome to come. I'll try not to talk about business. And I am too cheap to gamble even one penny.

Make as much money as you can while you can and have fun doing it.

Jack

[Service Guy]

There is more psychology to pricing that business. Yesterday, I signed a contract to replace drains for $5400. The customer went under the house and had lights set up before I arrived so he knew what his problems were before I arrived. The customer said the price was lower than he expected.

There is a lot to be learned about perceived value. I used to think perceived value was deceived value. It goes far beyond just making your company look good or trying to majke a job look larger and better. There is a method to learn to build your perceived value so that your customers will not want to do business with any other plumber. The best customers you can have want the best job. The thrifty customers always seem to be problem customers before or after the job is finished.


I agree, good post.

[DuckButter]

Jack (Leonard?),

One thing to consider regarding your statement that the reduction in pressure at the tank was only a temporary fix...

Service guy brings to light the fact that plumbing & fixtures are made with 80psi in mind as a max regular operating pressure.

Though we all know they're tested substantially higher, they're not made to function at high pressure regularly.

When a water heater creats thermal expansion in excess of the rating, it really isn't expected that standard plumbing & fixtures will operate normally.

An analogy might be a light breeze blowing through a flute...very little noise, but when a person blows into it with a little force...you get noise.

I DO think you have a good point, but I don't think completely discounting the effectiveness of an expansion tank is the best idea either...other wise you might find yourself running around a home replacing or repairing fixtures unnecessarily.

[PLUMBER RICK]

i don't know about the rest of the country, but out here our water meters don't have check valves. thermal expansion goes back into the city main as long as the pressure before the regulator is less then the relief valve.

pressure regulators have a thermal relief bypass built into them. unless there is a back flow preventer installed in the system, the excess pressure will go back.

i know from my list of customers that less than 1% of them have an expansion tank. the only ones that do is because they have circulating pumps with a cold water check valve. thus making it a "real" closed system.

the purpose of an expansion tank is not for water hammer. it's for thermal expansion. sure it will absorb some hammer, by th way it's designed. but so will an old time air chamber that is still found in old homes.

any quick acting valve will create a shock wave. proper strapping will help minimize and so will reducing the pressure of the water.

just last month i had to repair a pvc sch80 line that developed a leak on the pressure side of the irrigation main. the 90 at the change of direction actually swelled and the joint was leaking. this is on a 4 year old outside above ground unrestrained system that was installed by the landscaper. the static pressure was 120#. but when the automatic valves would shut off the pressure spiked above 300# on my high end liquid filled instrument gauge. this spiked would happen 6 times a day with the 6 valve stations.

i'm surprised that plastic solenoid valves have not been destroyed yet. the plastic ones typically leak between the halves around the screws.

the fix is either a pressure regulator, a water hammer arrestor, or slow closing valves which are very spendy. an expansion tank will help, but not designed for the sudden shock wave. the internal rubber bladder is designed for slow expansion, not shock waves.

and it took 3 tries to get the 90 to hold. used primer and red hot glue. even bought new glue the second and third attempt. i left the water off for over 24 hours and it would start to leak less than 1 week later. i advised them to replace with copper as this plastic is not rated for outdoor uv. and the pipe is resting on top of the concrete.


rick.

[Service Guy]

.

the purpose of an expansion tank is not for water hammer. it's for thermal expansion.

No duh, that is why its called a thermal expansion tank! They are required by code in any closed system, here on any house with a city water meter. Many and eventually all the meters (in this area) have backflow preventers.

[ToUtahNow]

Most areas are installing dual checks at the meter yoke when installing new meters.

Mark

[Arts Cabinets]

Jack (Leonard?),

One thing to consider regarding your statement that the reduction in pressure at the tank was only a temporary fix...

Service guy brings to light the fact that plumbing & fixtures are made with 80psi in mind as a max regular operating pressure.

Though we all know they're tested substantially higher, they're not made to function at high pressure regularly.

When a water heater creats thermal expansion in excess of the rating, it really isn't expected that standard plumbing & fixtures will operate normally.

An analogy might be a light breeze blowing through a flute...very little noise, but when a person blows into it with a little force...you get noise.

I DO think you have a good point, but I don't think completely discounting the effectiveness of an expansion tank is the best idea either...other wise you might find yourself running around a home replacing or repairing fixtures unnecessarily.

You just might be right. Got me baffled!

Jack

[Masterplumb]

For those that said to remove some pressure from the expansion tank.

http://www.amtrol.com/pdf/MC4090%2006_07%20TXT%20Brochure.pdf

Go to page 8. On the bottom of diagram #3 (to the left of the w/h) there is a note about what the pressure should be. Psi must always match the incoming city water pressure or reduced pressure :rolling-eyes: . Nah, we don't need those stupid directions.

[JCsPlumbing]

I've read the directions too and have always set the pressure as you state but...... what else are you gonna' do if this solves the problem?

J.C.

[Masterplumb]

The reason it is important to match the pressure is so it can expand when the water is heated. If the pressure in the tank is at 40 and the pressure on the domestic is 60 you just lost 1/3 of your expansion capabilities.

[JCsPlumbing]

I know. But.....is it ok to "give up" this bit of expansion to solve the problem?

J.C.

[Masterplumb]

It is a temporary fix. do you think that Amtrol put that in their directions because they had a surplus of ink?

[JCsPlumbing]

It is a temporary fix. do you think that Amtrol put that in their directions because they had a surplus of ink?

No I don't. Why do you ask?

Just trying to get a feel for the problem and best way to correct it if I run into it. I'm not an Amtrol engineer and wonder if this is a definite or a manufacturers suggestion. That's why I was asking. I've never ran into such a problem and have always set a TXT by the manufacturers literature.

J.C.

[Masterplumb]

No I don't. Why do you ask?

Just trying to get a feel for the problem and best way to correct it if I run into it. I'm not an Amtrol engineer and wonder if this is a definite or a manufacturers suggestion. That's why I was asking. I've never ran into such a problem and have always set a TXT by the manufacturers literature.

J.C.

Picture the innards of the expansion tank. It is roughly half air and half water. If there is sixty pounds on the water side and 40 pounds on the air side, it is already compressing the air side (high pressure goes to low pressure) by roughly 1/3. There is now that much less room to expand.

If there is 60 pounds on both sides, the diaphram part is not pushing into the air side, so now there is the full capacity available for thermal expansion.

An expansion tank has absolutely nothing to do with banging in a domestic water system.

For those of you that are not matching the air side to the water side BEFORE installing the txt you are probably oversizing your tanks if it is working properly.

[JCsPlumbing]

Thanks. Good explanation.

Also, read post 30. He called Amtrol and they told him to lower the pressure lower than the static pressure to solve the problem.

Not good enough on the forum to know how to quote that small part. :o

J.C.

[Masterplumb]

Thanks. Good explanation.

Also, read post 30. He called Amtrol and they told him to lower the pressure lower than the static pressure to solve the problem.

Not good enough on the forum to know how to quote that small part. :o

J.C.

I dont know how to do that either! Not sure why a C.S.R. would tell them that, it is absolutely incorrect though. I think the engineers that designed the tank might have a little better idea on how it works though;)

[DuckButter]

Thanks. Good explanation.

Also, read post 30. He called Amtrol and they told him to lower the pressure lower than the static pressure to solve the problem.

Not good enough on the forum to know how to quote that small part. :o

J.C.

I was going to say it, you beat me to the punch.
MP is prolly right that the tank is oversized, but better that than the other way around with no room for play.

[ridgidpipe]

Thanks for all replys! I hate to go to traditional hosebibs after talking up the ones I installed , my customers love em, I'm a hero. According to the installation instructions the air pressure is supposed to to the same as incoming water pressure but I also will take to heart the suggestion of lowering air pressure. Washing machines are not connected yet but I should simulate with the valves installed (Soiux Chief Ox Box w/ arrestors) good point.

Thanks,wookie

Im not sure you have to give up on the 1/4 turn hosebib valves your customers love.
Just take Service guys advice and next time put hammer arrestors between the shutoff valves and the hosebibs and that should take care of the problem in the future with the quick closing valves you like to use.

[Killertoiletspider]

And most of you think I'm nuts for putting an air chamber on every outlet...

[JCsPlumbing]

Air Chamber-YES

Hammer Arrestor on every fixture-YES :p

J.C.

[PLUMBER RICK]

any fast acting valve will create a surge. wait till he tries his washing machine and automatic sprinklers.

the ada ball valve hose bibbs are great. i always warn my customers to open slow and close slow.

i give them the same example as when they pull up to a stop light with their car. no putting the pedal to the metal and no slamming on the breaks. they get the idea:rolleyes:

un fortunately putting a vacuum breaker on those hose bibbs really choke down the flow.

there are newer arrowhead hose bibbs with an internal vacuum breaker that flows better and doesn't chatter. it can be identified by its yellow handle. the vac breaker is in the stem assy;)

rick.

Im not sure you have to give up on the 1/4 turn hosebib valves your customers love.
Just take Service guys advice and next time put hammer arrestors between the shutoff valves and the hosebibs and that should take care of the problem in the future with the quick closing valves you like to use.

absolutely correct. if the customer is going to slam open a 3/4'' full port ball valve and slam it shut, they are going to get water hammer.

just like i stated on post 28, train/ teach the customer to open and close slowly. we all know never slam a valve open or close. we don't do it, the customer shouldn't do it.

if they truly have pipes that are not properly strapped, then that's a different story. but i know for a fact every quick acting valve will create a hammer effect.

rick.

[Masterplumb]

Air Chamber-YES

Hammer Arrestor on every fixture-YES :p

J.C.

O.k I hope this is not the start of another one but..... air chambers are useless. They fill up with water in a very short amount of time and are just a place for stagnet water.

[DuckButter]

And most of you think I'm nuts for putting an air chamber on every outlet...

No, your just nuts....in a good way of course.:rolleyes:

[DuckButter]

O.k I hope this is not the start of another one but..... air chambers are useless. They fill up with water in a very short amount of time and are just a place for stagnet water.

This could get ugly, but I see no reason for it to.
We are required to use air chambers here...I'm open to your experience or any lit you might have on it...what is the source of your info?

[Killertoiletspider]

O.k I hope this is not the start of another one but..... air chambers are useless. They fill up with water in a very short amount of time and are just a place for stagnet water.

How much stagnant water can you collect in a twelve inch long piece of half inch pipe?

We have high rise buildings here that have over a hundred psi on some floors, and have no issues with water hammer, yet I read posts on these forums of water hammer with pressures much lower than that. Can you explain to me how this can happen?

[Masterplumb]

How much stagnant water can you collect in a twelve inch long piece of half inch pipe?

We have high rise buildings here that have over a hundred psi on some floors, and have no issues with water hammer, yet I read posts on these forums of water hammer with pressures much lower than that. Can you explain to me how this can happen?

I "assume" from previous posts where we "talked" that you do new work and not service. I guess you have never had to drain a riser in one of those buildings so the riser can refill with air to stop water hammer, I have. I'm not looking to get into it, I'm just going by experience in service work in apartment buildings and high rises.

Just because the air chambers are installed does not necessarily mean that is the reason there is no hammer. It may have not needed one to begin with. Many of the older buildings here have them, they dont work period.

Read this non-believers

http://www.siouxchief.com/Frm_MS.cfm

Ok bad link heres the page

http://www.siouxchief.com/images/bbwhfoac.jpg

http://www.siouxchief.com/images/waterhmr.jpg

http://www.siouxchief.com/images/airchmbr.gif

The fallacy of air chambers
It used to be thought that an air chamber, or capped stand-pipe, was an effective solution to controlling water hammer. However, within an air chamber, nothing separates the air from the water. It only takes a few short weeks before the air is absorbed into the water, leaving the air chamber waterlogged and completely ineffective. Laboratory tests confirm that the air is depleted by simple air permeation and by interaction between static pressure and flow pressure.

Engineered water hammer arresters
Engineered arresters use gas or air to control water hammer. Unlike the air chamber, gas or air in an engineered arrester is permanatly sealed with a piston.

[Killertoiletspider]

I "assume" from previous posts where we "talked" that you do new work and not service. I guess you have never had to drain a riser in one of those buildings so the riser can refill with air to stop water hammer, I have. I'm not looking to get into it, I'm just going by experience in service work in apartment buildings and high rises.

Just because the air chambers are installed does not necessarily mean that is the reason there is no hammer. It may have not needed one to begin with. Many of the older buildings here have them, they dont work period.

Read this non-believers

http://www.siouxchief.com/Frm_MS.cfm

I do remodel work in high rise buildings, some of them were built in the twenties. You would never have to shut a riser down to restore air to any given floor, they are valved on every floor, and have to be by code.

Your link offers nothing to support your misguided statement, so you are going to have to come up with some better support.

[JCsPlumbing]

I have never worked in a high rise. I understand some of the plumbing principles though. At least sometimes. :rolleyes:

As Masterplumb states, if the risers were needed they would constantly have to be maintained because of waterlogging.

Do you guys that work on high rises drain them down on a regular schedule? EVERY high rise? If not, why not? You should be getting calls to do a shutdown/draindown, right? They ARE waterlogged or will be from what I understand.

A building is constantly going through pressure changes isn't it? And that would probably remove the need for the risers. What I mean is 5 people on one part of the system turn something off or have a solenoid shut while say....7 people on the same part of the system are turning something on or a solenoid is opening cancelling the hammer. That in conjunction with expansion tanks, meters without check valves etc.

Does this sound right? Seriously, FEED THE SPONGE!

J.C.

[Masterplumb]

I do remodel work in high rise buildings, some of them were built in the twenties. You would never have to shut a riser down to restore air to any given floor, they are valved on every floor, and have to be by code.

Your link offers nothing to support your misguided statement, so you are going to have to come up with some better support.

they are valved at every floor that is correct, BUT in order the PROPERLY drain an air chamber on the end of the riser you must shut the riser and drain the line, that is fact.

An air chamber WILL fill with water and lose the air in "the chamber" that is fact.

Just because something is there and has been there for 80+ years doesnt mean it is correct.

[Masterplumb]

I have never worked in a high rise. I understand some of the plumbing principles though. At least sometimes. :rolleyes:

As Masterplumb states, if the risers were needed they would constantly have to be maintained because of waterlogging.

Do you guys that work on high rises drain them down on a regular schedule? EVERY high rise? If not, why not? You should be getting calls to do a shutdown/draindown, right? They ARE waterlogged or will be from what I understand.

A building is constantly going through pressure changes isn't it? And that would probably remove the need for the risers. What I mean is 5 people on one part of the system turn something off or have a solenoid shut while say....7 people on the same part of the system are turning something on or a solenoid is opening cancelling the hammer. That in conjunction with expansion tanks, meters without check valves etc.

Does this sound right? Seriously, FEED THE SPONGE!

J.C.

I have had to drain the risers in buildings many times to stop water hammer. I have many buildings that I have never had to drain down either, most likely because there is not a situation present where there would be hammer even without the chamber.

[Killertoiletspider]

they are valved at every floor that is correct, BUT in order the PROPERLY drain an air chamber on the end of the riser you must shut the riser and drain the line, that is fact.

An air chamber WILL fill with water and lose the air in "the chamber" that is fact.

Just because something is there and has been there for 80+ years doesnt mean it is correct.

A vacuum pump works just fine without draining down the riser.

And JC, it takes years to waterlog an air chamber under normal working pressure (normal being anywhere between 40 to 70 PSI) anything above normal requires more maintenance or installing a prv on the riser.

[Masterplumb]

A vacuum pump works just fine without draining down the riser.

And JC, it takes years to waterlog an air chamber under normal working pressure (normal being anywhere between 40 to 70 PSI) anything above normal requires more maintenance or installing a prv on the riser.

Traditional Solution to Water Hammer

Traditionally, the solution to water hammer has been to install pipe risers inside the wall at each faucet or valve junction. Sometimes these risers would be as high as 24" or more, depending on the pipe diameter. In theory, the risers would trap air as the plumbing system is first activated. The column of air acts as a natural damper, compressing as it absorbs residual shock waves from a sudden change in the supply flow.
Many, if not most older homes today have such systems and some plumbers continue to install air risers because "that's the way they've always done it." However, what is not readily understood is that these risers eventually fail due to water logging. Over time, the trapped air in the risers dissolves into the water supply itself and the water level gradually rises until the air chamber is completely void of air at all. For this reason, some people who have never experienced the sound of water hammer may suddenly start complaining of "strange noises inside the walls."
The only real solution is to completely drain the home's water supply system at the lowest point and gradually re-pressurize it. However, this solution is temporary at best, since the air chambers will eventually become waterlogged once again, thereby eliminating their effectiveness.
What's more, further studies have also found possible health problems associated with air risers, such as an accumulation of rancid water, bacteria, minerals, and other muck that festers in the dark, dead-end chambers. If left unchecked and untreated, this could eventually contaminate the entire household water supply causing unexplained illness.
Therefore, modern practice and, indeed, many plumbing codes, now prohibit air chambers in new construction. In any case, if you are remodeling or building a new home, DO NOT use air chambers to mitigate water hammer problems. Rather, design the system right from the start and you'll never have to worry about it again. A combination of proper pipe sizing and water hammer arresters are all that's necessary in most situations.

[Masterplumb]

Heres another

http://www.psdmagazine.com/pdf/Mar_Apr_05/52_53.pdf

[Killertoiletspider]

Heres another

http://www.psdmagazine.com/pdf/Mar_Apr_05/52_53.pdf

To support your position by posting info supplied by the manufacturer's of mechanical water hammer arrestors means you have no real knowledge on the subject, and are simply going by what you have been sold by biased opinion, but hey, if it works for you run with it.

I have almost a hundred years of proven service on my side.

[JCsPlumbing]

Maybe I'll conduct an experiment with a Wirsbo Riser to figure a time for waterlogging. Sounds crazy but if you have an air/water separation in the pipe you can see it.

Things to do. Hmmmmm :rolleyes:

J.C.

[JCsPlumbing]

People used to think the world was flat too. :wave:

J.C.

[Masterplumb]

Another one to support my cockamamie idea



Don’t come a knockin’
Water hammer implications, complications and troubleshooting
BY CHUCK LOTT,
contributing writer
Water hammer has been around ever since man began forcing non-compressible liquids (typically water) through non-expandable conduits (name your pipe). The Romans and their aqueducts never had to deal with the problem, but as man began routing water through pipe in ever more complex ways, the destructive force of water hammer soon followed. The problem arises each time a flow of water is abruptly halted by a quick closing valve in a confined space.
All fluids in motion contain a tremendous amount of energy (hydroelectric power being the foremost example). This latent kinetic energy moves peacefully through a piping system along with the flow of water until it is required to stop. If flow is eased to a stop by a slow closing valve, the associated energy is slowly dissipated and easily absorbed by the system. If flow is abruptly halted by the slamming shut of a quick closing valve, the energy generated by the closure becomes destructive if not otherwise put in check. Pressure spikes of several hundred pounds are not uncommon in systems nominally measured at 60 to 80 psi. Constant exposure to pressure spikes of this magnitude will wreck havoc on fittings and fixtures anywhere in proximity. In addition to potential system damage, water hammer is often accompanied by a very audible and disturbing “BANG.”
So, what to do? Years ago a common solution was to install a simple standpipe in the vicinity of the quick acting valve. This upright standpipe (commonly referred to as an air chamber) simply retained a pocket of air when the system was filled. As water hammer was generated, the shock wave found this compressible air pocket allowing the water to expand into the chamber, thus dissipating its energy. The downside to this solution is that in a matter of weeks air chambers fill with water, completely eliminating any efficacy they may have originally provided.
Today’s solution to effectively manage water hammer is engineered water hammer arrestors. They are typically a nitrogen-charged, piston-style design, though you may still see bellows type arrestors on commercial projects. Though both designs are conceptually similar to air chambers (a nitrogen pre-charge to absorb energy), both the piston and bellows design differentiate themselves from the old air chamber in one critical area……….the dry nitrogen charge and system fluid are separated by a physical barrier. Barring catastrophic failure, piston arrestors will rarely lose their nitrogen charge, fill with water and lose their effectiveness. In fact, some manufacturers warrant their piston-style water hammer arrestors for the life of the plumbing system.
Installing water hammer arrestors is a fairly simple exercise, provided you remember two critical elements: The arrestor must be properly sized for the job, and placement must be in immediate proximity to the quick closing valve. Sizing for multiple fixtures on commercial projects is easily determined by use of the standardized Plumbing and Drainage Institute’s (pdi) water hammer arrestor sizing guide. Here you will find fixture types and the weight in fixture units for each valve. It’s then a simple matter of adding fixture units to determine water hammer arrestor size (A through F). Sizing residential arrestors (AA) is simpler yet, in that they are designed for single valve applications only; one valve equals one water hammer arrestor. Regarding location, most manufacturers agree that if you’re much further than six to eight feet away from the shock source, you have lost much of the protection the water hammer arrestor was designed to provide.
In troubleshooting water hammer complaints, probably the most vexing question is determining whether you have a water hammer problem at all. If any inexplicable noise can be detected anywhere throughout a plumbing system, I guarantee you it will be diagnosed as water hammer. In fact, most noisy piping systems are noisy because they have not been properly tied down. The kinetic energy I referred to earlier is present when flow begins in a system just as it is when it stops. If pressure piping is not adequately secured during flow conditions, it will want to move, just as a lightweight garden hose would with the hose bib wide open in your backyard. A water hammer arrestor will not remedy this. Secure pipe will. Water hammer is a specific, repeatable occurrence. It manifests itself only when a quick acting valve closes in a pressure piping system. Damage and noise will be localized upstream of the shock source and can be repeated each time the valve closes. Under these conditions, a properly sized water hammer arrestor placed just before the problem valve will provide the perfect solution to your water hammer dilemma.

[Masterplumb]

Try page 13 here

http://www.copper.com.au/uploaddir/documents/WaterHammerBook_V2.pdf


Could it be the union and its hundreds of years experience is wrong?

[Killertoiletspider]

You really should find at least ten more sources funded by the manufacturer's of mechanical hammer arrestors, it will really help fuel your argument.

I'm done on this subject.

[Service Guy]

I agree with masterplumb. My first new york shop did old school, dead-end air chambers, but they didn't last to long before needing to be drained. A proper hammer-arrestor device installed is a lot better than a dead-end air chamber, since they don't get water-logged.

[JCsPlumbing]

You really should find at least ten more sources funded by the manufacturer's of mechanical hammer arrestors, it will really help fuel your argument.

I'm done on this subject.

It's just common sense without one manufacturers source. Be open minded that you could be wrong.

Heck, I didn't know what a Sission Joint was!

J.C.

[Masterplumb]

It's just common sense without one manufacturers source. Be open minded that you could be wrong.

Heck, I didn't know what a Sission Joint was!

J.C.

Aint gonna happen. Thats why he is done talking about it. He'd rather hurl insults at me then admit he's wrong. I've seen that type before.

[Service Guy]

Aint gonna happen.

Like you're any different, hard-head!:banghead: :rolleyes:

(just kidding around:D)

[Masterplumb]

You really should find at least ten more sources funded by the manufacturer's of mechanical hammer arrestors, it will really help fuel your argument.

I'm done on this subject.

If air chambers worked, would manufacturers spend tons of money in researching water hammer to come up with a product that actually works. Why re-invent the wheel if they work? Maybe your ua classes were wrong?

[JCsPlumbing]

:rotflmao1:So true Carl! Every plumber!

I always tell people if I want to know about ANYTHING I can just go to the supply house counter because every S.O.B. there knows EVERYTHING!

With confidence too! :smack-head:

J.C.

[DuckButter]

Not to "join sides" on any personal level, I will say I'm partial to the fact that much of the research offered by MP could likely be biased (Think big business, pharmaceuticals for example).
But the sheer number of reports he's offered has me questioning the effectiveness of chambers.
As long as my code requires them, the topic is moot, but certainly food for thought.

[Masterplumb]

Like you're any different, hard-head!:banghead: :rolleyes:

(just kidding around:D)

Carl, you dont always have to state you are kidding around every time you rib me. I get passionate about things but I DO know how to take a joke.:clapping:

[plumberjr]

hello-new to the site-
had the same problem with same type of valves-i removed them and installed regular fp sills and problem solved:)i dont even think arrestors will help you

[Masterplumb]

Not to "join sides" on any personal level, I will say I'm partial to the fact that much of the research offered by MP could likely be biased (Think big business, pharmaceuticals for example).
But the sheer number of reports he's offered has me questioning the effectiveness of chambers.
As long as my code requires them, the topic is moot, but certainly food for thought.

There was only one article, the first one, that was by a manufacturer (sioux chief) and I agree it could be biased, but thats why I gave other articles.:grin-angelic:

[JCsPlumbing]

WHERE WERE YOU 80 POSTS AGO!?!?:mad:

J.C.

[JCsPlumbing]

I think I've got too much pressure on my brain. Should I put an expansion tank on my azz?

What pressure?:rotflmao1:

J.C.

[DuckButter]

OK, 'nuff already...the mrs just came in and gave me a hearty scolding...you guys are making me miss our Red Sox game...she now knows it's YOU guys fault...back later.

[wookie]

Really enjoying the discussion, my customer understands the proper opening/ closing of the hosebibs I installed and is ok with it. I've decided to add arrestors on the hosebibs, it just seems proper thing to do. I'll re up the expansion tank and test. If again I get the pipe vibrations I'll lower again. I still believe tank and incoming pressures should be equal per instructions but can't have what I was getting with the water pipe vibrations. When talking to Amtrol tech support I told them I knew some "other plumbers" who suggested lowering the air pressure and support said " I was just going to suggest that also" . What can I say. I believe I did good work on this caper and to me an unusual problem developed that has been solved, not masked.

Thanks, wookie

[doubleD]

Install hammer arrestors on the hose-bibb lines after the ballvalves. It is weird that is goes away when the expnasion tank is removed, I don't think I have seen that before.

Hammer arrestors / shock stops would do the trick. I always try to put them on a straight run with the line thats getting the hammer.

[ridgidpipe]

By code here in Ohio we can not put on air chambers for the same reasons stated here by others on the forum they say they will collect stagnent water and there is a good chance for bacteria to collect in them. I dont know how true that is and have not done any experiments personally. But if thats what the code officials in my area enforce I will just stick with the proper hammer arrestors.