View Full Version : Another Water Hammer Question
here4more
08-08-2007, 10:05 AM
I experience water hammer whenever I flush the toilets furthest from the main and sometimes whenever I shut off the shower furthest from the main. This is a new house, 1 year old.
Some background: Watering lawn was difficult. Sprinklers attached to outside faucet barely rotated. Next door neighbor (home built at same time, same builder & plumber) has a sprinkler system and suggested adjusting the regulator (PVR???) to increase psi. Water pressure gauge shows neighbor’s psi is 80. I set mine to 80 as well. But my neighbor does not experience water hammer and I do.
We did not have water hammer prior to adjusting PSI but did experience poor performance. We are very comfortable with and enjoy the current pressure. The lawn gets completely watered and the shower feels great. Only problem is the water hammer. What to do?!?!?
geniescience
08-08-2007, 08:05 PM
hammer noise and vibration has to be treated. Several ways to do that. Have you already searched on this? Do you know where the hammer arrestors are in your house? How many?
David
here4more
08-09-2007, 08:06 AM
Thanks David for replying. This IS a GREAT forum! It was from this forum that I was able to understand technically what the noise is. I have searched the forum and have found several very good posts. However, I do not know where my hammer arrestors are in the house or how many I have, if any.
My questions: My house is on a 4 foot crawl space with all the plumbing under the house. Is this where my hammer arresters should be? Nothing in the house looks like the arrester pictures that I've seen.
Should I just decrease the PSI to eliminate the water hammer and suffer with the lower water pressure? Really it wasn’t so bad – perhaps I can find a happy medium? Or, should I install hammer arrestors on the toilets and shower? But, by doing the later, is it possible that I may still cause damage to my plumbing although I may not hear the water hammer?
Thanks Again.
GrumpyPlumber
08-09-2007, 08:39 AM
I'm going to have to guess the plumber never installed an expansion tank with the PRV.
I had this EXACT same problem with a customer last month...simple expansion tank fixed it perfectly.
GrumpyPlumber
08-09-2007, 08:40 AM
Also....IF there's an expansion tank...it's not likely pressurized to match the systems 80 psi.
here4more
08-09-2007, 08:48 AM
If you haven't figured it out by now, I'm a total plumbing n00b. I do know that i have what looks like a gallon container turn outside down sitting on top of my gas hot water heater. I believe it says potable expansion tank. Is this what your talking about? How do I pressurize it to match the 80psi?
GrumpyPlumber
08-09-2007, 08:58 AM
If you haven't figured it out by now, I'm a total plumbing n00b. I do know that i have what looks like a gallon container turn outside down sitting on top of my gas hot water heater. I believe it says potable expansion tank. Is this what your talking about? How do I pressurize it to match the 80psi?
Thats it...get a tire guage...take off the small plastic cap on the bottom and check the pressure.
IF it's less than 80...get a bike pump and eat yer wheaties.
here4more
08-09-2007, 09:01 AM
Thanks! I'll try it and report back tomorrow!
Mr_Pike
08-09-2007, 10:43 AM
Thats it...get a tire guage...take off the small plastic cap on the bottom and check the pressure.
IF it's less than 80...get a bike pump and eat yer wheaties.
You should try borrowing or stealing an aircompressor first, Grumpy may be trying to kill you!
GrumpyPlumber
08-09-2007, 10:47 AM
You should try borrowing or stealing an aircompressor first, Grumpy may be trying to kill you!
Dammit...DON'T ruin my fun!
here4more
08-09-2007, 11:16 AM
LOL))))))
Mr. Pike... I already figured out that I would use my aircompressor!
Thank you all for your assistance!!! I'll let you know how it turns out.
markts30
08-09-2007, 03:41 PM
I believe that before you pump it up, you have to release the pressure in the system...
Turn off the water and open a faucet...
Once that is done, close the faucet again and pump till you reach 75-80 psi...
Then turn the water back on....
GrumpyPlumber
08-09-2007, 10:26 PM
I believe that before you pump it up, you have to release the pressure in the system...
Turn off the water and open a faucet...
Once that is done, close the faucet again and pump till you reach 75-80 psi...
Then turn the water back on....
lol...er...yea, that too...it'll read 80 psi if ya don't...oops.
Old Dog
08-09-2007, 11:31 PM
IF it's less than 80...get a bike pump and eat yer wheaties.
80 with a bike pump?I'd get a couple of cans of spinach to go with them wheaties...lol
GrumpyPlumber
08-10-2007, 11:33 AM
80 with a bike pump?I'd get a couple of cans of spinach to go with them wheaties...lol
Don't laugh...it's right in the instructions on the Amtrol/Diatrol tanks manual...bike tires inflate to an excess of 100 psi in some cases.
Though I prefer to say I'm just a big tough guy....yeah...thats it.
Wet_Boots
08-10-2007, 01:00 PM
I pressurized an old galzanized well-water tank with a bicycle pump once. It isn't the sort of thing you want to do twice.
jadnashua
08-10-2007, 02:00 PM
Yes, but, that's sort of like trying to inflate a massive truck tire verses a bike tire...an expansion tank has a quite small air volume.
GrumpyPlumber
08-10-2007, 07:10 PM
Yes, but, that's sort of like trying to inflate a massive truck tire verses a bike tire...an expansion tank has a quite small air volume.
Exactly....welltrol's are 40+ gallons...expansion tank might be 2
Old Dog
08-10-2007, 09:31 PM
Don't laugh...it's right in the instructions on the Amtrol/Diatrol tanks manual...bike tires inflate to an excess of 100 psi in some cases.
Though I prefer to say I'm just a big tough guy....yeah...thats it.
Grumpy,
For some reason I was thinking of the small pump that snaps on the bike frame...and a very large pressure tank!
(BIG,TOUGH,AND GRUMPY... REMIND ME NOT TO P**S YOU OFF)
GrumpyPlumber
08-10-2007, 09:44 PM
Grumpy,
For some reason I was thinking of the small pump that snaps on the bike frame...and a very large pressure tank!
(BIG,TOUGH,AND GRUMPY... REMIND ME NOT TO P**S YOU OFF)
Naah...in fact the "Grumpy" name was intended as a humorous antonym...ssshhh, don't tell anyone, I got a reputation to keep.
You should meet my sweety though...5 feet, 2 inches of raw fury.
Kilgore!!!!
08-31-2007, 11:24 PM
I was thinking immediately that the long run of pipe on the distant side of his house from the water main is "typical water hammer at its finest." You get water at 8.3 lbs per gallon moving down a long run and suddenly shut the water off= Bammm! Like a water sledgehammer.
Would the expansion tank help relieve this?