weird water heater leak - Atwood

[Henry's RV]

My last trip, I hooked up to the water, turned it on, and water started dripping, heavily, out of the water heater. Took the compartment cover off, checked and tightened all fittings, turned water on again, still leaking. Shortened my trip and returned home due to no hot water. I had a service appointment for other things so told them about the water heater leak. No leak for them. Filled it up, turned it on, heated fine, and absolutely no leak. What the...? The leak I saw came from between the Styrofoam insulation pieces around the heater, so I'm guessing a weld, or perhaps that is just the only place for the water to get out. I have asked dealer to drain tank, refill, heat, and go through the process one more time to see if leak will return.

I am baffled, as are they. This was a pretty hefty leak, enough that the heater could not be turned on as it was not holding water, not a pinpoint. The only thing I can think of is some sediment plugged a leak? Although this is a new unit, only 3 short trips, in service just 2 months, so not likely to have any sediment. I don't want to get out on the road and have this happen again. Hoping someone here has some suggestions as to either what happened, or what to try to make sure the unit is functioning properly. Many thanks for any and all ideas!

[Moparguy62]

First make sure the heater is full (pull the leaver on pressure relief valve) then make sure the lower pan inside the wtr htr door is caulked its a two piece flange and must be caulked. The tanks never reseal them selves. Sometimes they have cold leaks and go away once heated, this includes the back flow preventers on inlet and outlet.

[blw2]

not directly an answer, but maybe food for thought
I had a leaking relief valve once.
Read in the manual that this is considered normal.... when the air bubble in the heater dissipates, the expanding water has no place to go so the relief valve opens
The solution is to burp in some air.

Maybe when your leak was happening the tank was full.... meaning the air bubble that would exist in your tank was gone. Then through goofing around with it you reintroduced some air so the water could expand without leaking.

I think you need to put a pressure gauge on the tank (or hot water side), pressurize it, and shut off everything to see if the pressure does in fact leak down.

[blw2]

maybe you were only seeing the leak because of the existing level or out of level situation.... then when the RV was moved the leak flows in a different direction so you no longer see it?

just brainstorming