Noise from Pressure Reducing Valve????

I had a pressure reducing value replaced because I had water discharging from my hot water heater. Now I have an extremely loud whistling noise (train horn) coming through the entire house and vibration. The noise and vibration appears to be coming from the new pressure reducing valve. Do I need to buy another pressure reducing valve? Or should I check the pressure first and record my readings then proceed from there. The noise has gotten progressively worse. I have a Watts N55B M1 ¾” installed with a union fitting then threaded onto cooper pipe. Any suggestions would be helpful.

Do you have a thermal expansion tank? If not, that would be the cause of your T/P on the water heater leaking. A thermal expansion tank and PRV go together because the PRV creates a closed system.

Did you check to make sure the inlet and outlet are in right direction?
A backward install will cause the noise.

yes there is a thermal expansion tank installed and the pressure valveis correctly installed in theright direction.

Check to make sure that there are no leaking toilets.
They can often make up a vibration almost like a water hammer.
Korky fill valves with just the right amount of leakage putting them right at where the valve turns on and off can make a huge amount of noise...
Probably a defective PRV...

Got me to thinking...

cwhyu2 said:

Did you check to make sure the inlet and outlet are in right direction?
A backward install will cause the noise.

Click to expand...

I unfortunately had to install my pressure reducing valve in such a way that I couldn't see the arrow marking flow direction, and somehow it must have gotten turned around in my hand. Used my phone to take a picture of the side I couldn't get to/see by putting my arm behind it, and sure enough, I had somehow turned the valve upside down. I'll flip it over and hope that the rushing water / clicking noise disappears and that the valve has not been damaged!

Feel stupid, but very glad I found this forum!

Update: Worked like a charm, and I even got the PRV facing the correct way this time around. No more whooshing noise. Thanks a bunch!