Hot water heater running pressure valve dripping - why?

[Ray1955]

Camping serviced said it was fine I think it runs to hot I'm in Maine it seems to b running now and pressure valve is dripping.
Thoughts please

[LostinAZ]

Water minerals corroding valve surfaces.

[larry_barnhart]

For a test last summer I removed our relief valve and soaked it in vinegar for 2 days. It looked new and not a drip for the 6 + months stay last winter. I do the same as the post above on getting the air chamber.
chevman

[83trekker]

Mine weeps when running its been just replaced and is new, does it because its expanding no problem I see with it.

[Norskeman]

I put an adjustable thermostat on our Atwood HW heater. Now instead of about 155 degrees it is 120 degrees.

[Old-Biscuit]

Per Manual:

PRESSURE-TEMPERATURE RELIEF VALVE
Weeping or dripping of a pressure-temperature relief valve while the water heater is running DOES NOT mean it is defective. This is normal expansion of water as it is heated in the closed water system of a recreation vehicle. The
Atwood water heater tank is designed with an internal air gap at the top of the tank to reduce the possibility of weeping and dripping. In time, the expanding water will absorb this air.
To replace the air follow these steps:
Step 1: Turn off water heater
Step 2: Turn off incoming water supply
Step 3: Open the closest hot water faucet in the coach
Step 4: Pull handle of pressure-temperature relief valve straight out and allow water to flow until it stops.
Step 5: Allow pressure-temperature relief valve to snap shut, turn on water supply and close faucet.

[Dog_Folks]

Our Atwood manual states that a small amount of "weeping" is normal. Check yours.

After fighting with it for a few years, I just let it weep.

[Allworth]

Crud!

[joelc]

The valve should not be dripping. When it is NOT under pressure check to see if something is caught in it like rust. If not just replace the valve. It should not drip.

[restlesswind]

I replaced the pr valve.No more dripping.
Mine took a standard household type,(Suburban water heater)bought it from the local Ace hardware store.
Use the method that bob213 suggested to refill/re-establish the air pocket.

[homedad]

I don't know how old your rv is but when my tp valve did the same I tried the air pocket thing. Ended up replacing the valve. Easy to replace but contrary to info on this site mine had to be ordered from an rv supply site as it was a different diameter than regular house water heater tp valves.

[bob213]

May need to re-establish the air pocket.
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.

[2oldman]

Open n close it a cupple time