Hot water tank temperature- pressure relief valve

You check to make sure this "leak" was not the very common, and easy to fix, "weeping" that occurs when the water tank loses its air gap?

Tom

Have had 2 rvs in my 9+ years fulltiming. Both pressure relief valves I've had have leaked. There are stories of fixing it by making sure air is in the tank (tried it...never worked). The best thing I have seen is attaching a hose to the prv and leading it out of the access panel to drip harmlessly on the ground. If you find a solution that works, post it here. I would be interested as mine still weeps.

if you got the tank out? heat the brass valve it,ll release the pipe dope. on reinstall use pipe tape. and make sure your turning it the right way.

New valve and a small shurflo expansion tank is my recommendation.

If it is stuck you just need a bigger wrench ;)

I fixed this problem by removing the valve and soaking it in vinegar for a couple days 3 winters ago and still using it. I soak the water system in vinegar and set for a couple of days and then drain and run water until it does not smell. Then redrain the water heater and flush it.

chevman

Many times as Pulsar suggested this will stop the leak:
1. Turn off the water heater.
2. Turn off the cold water supply line.
3. Open a faucet in the RV.
4. Pull out the handle of the pressure relief (P&T) valve and allow water to flow from the valve until it stops.
5. Release the handle on the P&T valve - it should snap closed.
6. Close the faucet and turn on the cold water supply. As the tank fills, the air pocket will develop. Repeat this procedure as often as needed to reduce the frequency of the weeping P&T valve.

TPRVs (Temp/Press Relief Valves) on RV Water Heaters leak due to scaling/calcium build up on valve/seat, will weep due to loss of air pocket on top of tank or because of high temps/pressures


With water supply on and tank cold you can open TPRV via lever allowing full water pressure to blow out and then let it snap closed by letting go of lever.
Do several times to clear valve/seat of build up

Air pocket by design
Hot outlet is lower than top of tank so that there is space for an air pocket.
Water expands when heated..water can not be compressed so w/o air pocket pressure will increase causing TPRV to weep

Air Pocket
Turn water supply OFF
Open closest faucet hotside to relieve pressure in hot water system
Open TPRV via lever......let it snap closed when water stops running out
Close faucet and turn on water supply




TPRV
Set to OPEN at 210*F, 150PSI -----rarely do they reach those conditions

Bad TPRV
Try tightening first then loosing
Sometimes it easier to break 'seal' by tightening
Easiest is to remove exhaust shielding so that you can get better access with wrench on 'flats'

BUT CAUTION:
Atwood uses an Aluminum Alloy Tank with aluminum threaded bungs
Suburban uses a Steel Tank with steel threaded bungs.....and inside of tank is glass-lined

Ours was weeping it was because the water pressure was 75-80psi. I installed a Watts regulator and set it to 60psi and all is well.

I just installed a Hybrid Heat element in our 6 gal Atwood. After I de-winterized for Easter weekend I was testing it out at home. The pressure relief valve was weeping pretty bad. I thought the valve was bad so I installed a new one. Sure enough that one leaks as well.
Until now I thought it was the additional Hybrid Heat element, I would never have guessed the air pocket and expansion.

Thanks for posting!

Mine was leaking about 5 years ago. I opened it and immediately closed it. Hasn't leaked since. Be careful of the hot water.