Water Heater Fitting Leaks

[dave89]

Earlier this year, I discovered water dripping from the inlet and outlet fittings to our water heater. It's an "Attwood GC6AA-10E" model. The camper is a Jayco 2013 x23b. I spent time replacing the plastic fittings that went into the heater with Teflon tape and pipe sealant. Worked great for the next two trips. Then last week as I was setting up, I noticed water seeping from under the panel where the water heater is located. Opened it up and found the bottom plastic fitting at the tank was leaking again. I tried to stop it by a bit of tightening but didn't want to go too far so without any luck. shut the water heater down and isolated the tank with the bypass. We went through the trip without hot water but managed.
This week I tackled the problem once and for all, I hope. After doing some research, I replaced the two plastic fittings with copper nipples. I beveled the inside of the nipple where the PEX connector screws on to it and reassembled everything. I pressurized the system and things looked good. With the pump off, I left it over night with just the residual pressure in the system. This morning I checked for leaks, none. I then turned on the pump which made no sound so as to refresh the system. I ran the water for several minutes to check for leaks. So far so good. The tank is now heating and we'll see how it does.
But I was wondering if anyone else has seen this issue. From what I've read, at one time, copper fittings were used from the tank to the PEX but about 8 years ago, due to cost and other things, they went to plastic.