View Full Version : Noise from PVB

11-16-2006, 05:49 PM
I am having a loud noise coming from my Pressure Vacuum Breaker that is in my basement. On the advice of a person at one of our large hardware outlets, I installed the air tank to the line thinking it would solve the problem. Is there a way to solve the noise? It is a vibration but I am not sure how to stop it. Thank you.

11-16-2006, 05:56 PM
Do you mean PRV (Pressure Reducing Valve)? If the PRV is making noise you need to replace it.

11-16-2006, 06:01 PM
The words Pressure Vacuum Breaker is what it is called here online by one of the sites related to this product. It keeps contaminated water from returning into the system from the yard sprinkler system.

11-16-2006, 07:34 PM
Is the air tank you installed an expansion tank? Have you tried replacing the vacume breaker?

Gary Swart
11-16-2006, 11:47 PM
The device you are describing is the backflow preventor. It should be inspected annually and repaired or replaced when not working properly. My city requires an annual inspection. The expansion tank is intended to absorb the expanded water from the water heater. It does not belong in the irrigation system.

11-17-2006, 06:42 AM
In an irrigation system it becomes an accumulator/water hammer arrestor. It prevents "reverse" water hammer when the valves open, and true water hammer when they close. But the only thing inside the valve that can vibrate without allowing water to spill on the floor, is the secondary seal, and it would only vibrate if there is a very small flow through the valve.

11-18-2006, 09:27 AM
I removed the expansion tank, because as you have helped me to understand, it is meant for hot water heater noise and not for irrigation systems. The noise is still there of course and probably from water in the line that is creating a noise where it enters the basement through the block wall. The pipe does touch the wall.
Thanks for everyones help.

11-18-2006, 10:47 AM
The expansion tank has nothing to do with noise at the water heater.

If you have a Check Valve and /or a Pressure Reducing Valve where the water enters your home, You need to put the expansion tank back.

11-27-2006, 09:44 PM
Okay...time for my two cents... expansion tank is for absorbing the pressure created by expanding water (or air ) when heated which otherwise would cause an unwanted rise in water pressure. Due to the similarity in nature and design it can also take over the function of a water hammer arrestor....
If the pipes touch the wall where they enter the house they need to have a sleeve around them so that the pipe can move freely. It can be sealed with a waterproofing material if needed as long as it doesn't prevent the movement of the pipe....this is code in lots of places. It will help prevent the transfering of vibration /banging/noise from the pipes to the house. Anyone who wants to correct me is welcome to...these are my thoughts only.