What sealant for plastic fittings?

[Rgraff]

My 2017 24RBS has developed a small leak at the cold water inlet to the water heater. Appears to be a straight forward repair but I am unfamiliar with plastic fittings. Assuming I can get it disassembled without breaking anything, can you recommend the proper sealant for reinstalling these plastic fittings?

Also, assuming worst case scenario in which the fittings are broken, is it recommended to replace with plastic again or brass? If plastic, should the replacement parts be, to any degree, heat resistant or will generic parts from a plumbing supply house be adequate?

For what it's worth this is an Atwood heater and the leak appears to be at the gray, square shaped fitting where it enters the aluminum. I can supply a pic if necessary.

Thanks in advance.

[norty1]

Here is a thread form awhile back that is still relevant: https://www.jaycoowners.com/forums/f...10e-95053.html

With the wh off and drained, you can remove the fitting that is leaking and use some pipe sealant or Teflon tape to reseal it. That area is prone to leak from vibration and heat changes.

[Grumpy]

Originally Posted by Rgraff

For what it's worth this is an Atwood heater and the leak appears to be at the gray, square shaped fitting where it enters the aluminum. I can supply a pic if necessary.

Thanks in advance.

That may be a check valve and if so I would replace it with the brass version.

[Randel J]

Teflon tape works excellent on plastic and PVC fittings.

[skids]

Originally Posted by Grumpy

That may be a check valve and if so I would replace it with the brass version.

Steel and aluminum are dissimilar metals leading to corrosion in the threads. I don't know about brass and aluminum (if you do as Grumpy advised), but I would do something at the thread contacts.

[ggilbert]

Use Teflon thread paste.

I had a leak in the same place. Nightmare to fix. Number one problem it was in a hard to reach location. Number 2 problem I broke the plastic nipple going into the hot water heater. Jayco being the geniuses they are some idiot use the white pvc nipples for cold water instead or the cream colored pvc for hot and cold water. So it cracked when removing and was basically glued in the hot water heater.

Start easy and tighten the pex fitting. If it still leaks change the cone washer

If I had it to do

I would try and replace the cone washer before anything else.

[ggilbert]

This was the thread with my troubles https://www.jaycoowners.com/forums/f...ves-93614.html

[skids]

Originally Posted by Rgraff

(snip)

For what it's worth this is an Atwood heater and the leak appears to be at the gray, square shaped fitting where it enters the aluminum. I can supply a pic if necessary.

I was thinking (without seeing it) that Jayco installed the check valve onto the water heater and then attached the pex pipe. If true, you would have to remove the pex hose from the fitting to remove the fitting from the water heater. If you are lucky you will have enough hose to cut it from the fitting
at the tank. If not, it might be a good location to install a union or maybe install a coupler and more hose. It is a bitch getting into that space to do that kind of work.

[billcf7]

Like Grumpy said I would replace the fitting/check valve, as these are prone to cracking

[Rgraff]

As luck would have it, the back side of my particular WH is pretty accessible. Sits directly underneath the refer and not hard to get to. The end of the cold water line attached at that fitting appears to be a "garden hose" type, screw on fitting crimped to the pex. I'm hoping to be able to unscrew the fitting without damage, remove the square shaped gray fitting from the tank, and replace it without too much heartache. As I mentioned, the leak is at the junction of the plastic, gray square and the aluminum tank.

If work doesn't get in the way, I'll locate available fittings at our local plumbing store (KIE) today and get to work on it. Thanks to all for the advice.

[ggilbert]

try the cone washer first. my camper did not have a gray piece there it has a white PCV cold water nipple.

[dave89]

I had the same issue a few years back. Seems that when I started the water heater on propane, it would warm too quickly for the plastic fittings to handle. I tried to seal then with both Teflon tape and pipe dope using new plastic fittings but again, when starting the heater on propane, the plastic fittings wouldn't seal on the water heater. I went to brass fittings on the water heater and haven't had any further issues. If you do decide to use the brass nipples on the heater, bevel the inside of the nipple where the plastic fitting will seat.

[Bayoutalker]

Originally Posted by Grumpy

That may be a check valve and if so I would replace it with the brass version.

I have a 2017 34rsbs and those fittings are just straight nipples, no check. Just remove and reseal with pipe sealant.