Leak from hot water heater

[work2fish]

Hi Folks,

I've been having a great time with my new camper this summer. I especially like that I can just stop anywhere to camp and do this on a whim since everything is packed and ready to go.

I noticed that when I had my hot water heater on, there is a constant dripping of water drops coming from one of the spigots, here:



It only drips when the hot water heater is on. I'm guessing that this is not normal, but the only way to fix it would be to put some sort of plug in that spigot. Can anybody tell me why this might be happening?

Thanks,
Mike

[westend]

I would bet that your relief valve is just slightly leaking, both water and air. After some time, the relief valve will bleed off the air and only water will remain.
These relief valves have an o-ring that is the usual cause of failure but it can also be a misaligned piston/seat or failed spring. I've had older ones fail with a single cycle of opening and closing.

[Rvpapa]

Go back and look at SMKETTNER's post.
Art.

[work2fish]

After camping over the past couple of days, the leak has returned. I followed the procedure once again to restore the air pocket and it stopped.

This makes me wonder if I am doing something wrong in terms of operation of the hot water heater. When I am camping, it is common for me to only turn on the hot water heater a few hours before I know I will need hot water. I will also draw hot water out of the tank even with the hot water heater in the "off" position as well. Do I need to leave my hot water heater in the "on" position the entire time I am camping? What sort of actions would cause the air pocket in the hot water heater to be eliminated?

[Harvard]

ronniedean1234 wrote:
.... you need to establish an air pocket at the top of the water heater for water to expand....

X 124

[work2fish]

The methods described in this post to restore the air gap in the tank worked perfectly. I followed the procedure and the leak stopped.

THANKS, FOLKS!

[bigB42]

look up building an air bubble on forums before replacing,the new one might do the same.very easy to do. ken

[time2roll]

Air pocket is a pain in the neck. Get a small ShurFlow expansion tank and never worry again.

If the leak truly is constant then most likely best to just get a new valve from your RV dealer.

[Clay_L]

The air pocket in the water heater may need replenishing.
The relief valve will tend to leak without it. The following is from the Atwood manual.

"To replace the air pocket start by turning off the water
heater, shut off the incoming water supply
and open the closest hot water faucet. Pull the
handle on the pressure-temperature relief valve
straight out to allow the water to flow from the top
part of the tank. Once the water has stopped
flowing allow the handle on the valve to snap shut,
close the faucet and re-engage the water supply."

[work2fish]

Excellent responses, thanks! I feel like a dummy for initially suggesting that I plug the valve to stop the leak but I learned a bunch about the hot water system through this thread. I will be looking at it this weekend and will post the results of what I find...

Thanks again,
Mike

[fla-gypsy]

There is nothing wrong with that pressure relief valve. It is doing exactly what it is designed to do. No need to waste time or money on it. Just drain the water from it next time before you go out to put the air pocket back in.

[nomad297]

That is a TEMPERATURE and pressure relief valve. It will relieve when the temperature reaches 210 degrees and when the pressure reaches 150psi. An RV plumbing system is so small that it doesn't take much for the expansion from heating water to reach 150psi which will cause the T&P valve to relieve. It could be that your water is too hot, but not likely. If this valve leaks continually, it may be worn out or the seat and washer may have hard water deposit buildup. Or, you may have a temperature or pressure problem. Replace the valve and see if it stops dripping. If it doesn't, work out why the pressure is so high or why the water is so hot.

Bruce

[Old-Biscuit]

ronniedean1234 wrote:
RV'S have a closed system, as the water heats it has to expand somewhere so out the relief valve it goes, you need to establish an air pocket at the top of the water heater for water to expand to, shut water heater off, shut incoming water off, open inside faucet and them open relief valve until water stops draining, shut relief valve then turn water on, then faucet off, the water heater does not draw the hot water off the top therefore leaves an air pocket in place, every once in awhile you need to replenish the air pocket....

As mentioned never put a plug into the p/t valve

X2

Air pocket on top of tank allows for the expansion of water when it is heated.
PRVs will weep when air pocket is lost and water heated.

As suggested.....re-establish the air pocket

[AnEv942]

Surprised no ones suggested trying to reestablish air gap? That and flushing. Couple of threads in the TCU under appliances.

The pressure/ temperature relief valves do fail or stuff gets lodged on the seat, sometimes opening, letting the handle snap close will seat. Sometimes not. But sometimes, though Ive not experienced, if no air pocket in tank, as water wont compress, pressure can cause valve to weep.
They are generic standard valves but many RVs use 1/2" threaded base, which isn't so common and can be hard to find localy at a hardware store.

EDIT: I type to slow..

[Canadian_Rainbi]

I'm surprised that no one has mentioned this:

The pressure relief valve can also leak when the airspace in the tank is gone. There should be air above the valve to allow for expansion when the water is heated. If no airspace then the expanded water is forced out the pressure relief valve.

To ensure a proper air chamber: Shut of water to system (either at the tap if on city water or turn off the pump. Open the pressure relief valve and a hot water tap at a sink. If no water runs out, the air chamber is OK and there is another problem, likely the valve. IF water runs out wait until the water stops running,close valve, turn off hot water tap then turn on the water pump or the city water. This procedure will restore the air in the tank.