Water Heater Leakage

[mikec557]

Okay, I forgot to drain anything nor use any Antifreeze. But in my defense, I'm in Sun City West AZ and the only "freezing weather" we've had was a few mornings that caused frost damage to some sensitive plants.

All that said, I've got a question and some pictures. I haven't brought the RV home to test the water system yet but I crawled into the crawl space and took the below pictures. The tank is full of water and some water appears to have leaked out through the cold water inlet. There's white powdery residue on the floor from the leakage. It would appear that the check valve is on the hot water out line at the top of the heater. So the white plug in these pics looks to be just a 1/2 inch NPT to Pex connector. It also seems to be a sort of white pipe dope around the plug. Or at least a white sludge around the plug.

After taking these pics I drained the water tank. No way to be sure, but it looked like most of 6 gallons drained out with no sign of white residue. Plan is to bring it home to check and test on March 9th.

What do you think the dry white residue is in the crawl space?

[GaryUT]

It looks to me like the hot water connection is where the leak is. In the gap in the styrofoam you can see where water has run down the tank.



Do you have any photos that show the hot connection?

[JRTJH]

My "guess" would be that the hot water "anti-flow valve" is leaking at the top connection. The bottom, cold water connection in your photos isn't very "healthy looking" either.

I'd suspect that this is not related to the "freeze last week". That water stain and the floor with "white residue" appears to have been wet for much longer than a few days or weeks. I'd suspect this is an "old leak" that's been dripping for quite a while, maybe even since the trailer was new.

I'd disconnect both hot and cold lines, recrimp the hose (or use clamps) and use Teflon tape on the threads (rather than "pipe dope). While you've got it apart, I'd go ahead and replace the "anti-flow valve". They are notorious for sticking (either open or closed) and being in Arizona, the "hard water there" won't do that valve any favors.....

[mikec557]

Originally Posted by GaryUT

It looks to me like the hot water connection is where the leak is. In the gap in the styrofoam you can see where water has run down the tank.

Do you have any photos that show the hot connection?

Ut oh. Yes, here's two pics of the hot water out line... It looks like it's leaking too.

[mikec557]

Originally Posted by JRTJH

My "guess" would be that the hot water "anti-flow valve" is leaking at the top connection. The bottom, cold water connection in your photos isn't very "healthy looking" either.

I'd suspect that this is not related to the "freeze last week". That water stain and the floor with "white residue" appears to have been wet for much longer than a few days or weeks. I'd suspect this is an "old leak" that's been dripping for quite a while, maybe even since the trailer was new.

I'd disconnect both hot and cold lines, recrimp the hose (or use clamps) and use Teflon tape on the threads (rather than "pipe dope). While you've got it apart, I'd go ahead and replace the "anti-flow valve". They are notorious for sticking (either open or closed) and being in Arizona, the "hard water there" won't do that valve any favors.....

Thanks JR. I posted two new pics above.


I recall reading that it's a bad idea to screw a different metal type (brass check valve) into the aluminum tank... something about electrolysis or corrosion? I see the oem is plastic rather than metal. Do you suppose that's just a cost savings or electrolysis concern?

What would you do, plastic (if I can find it) or brass?

I'm not sure I can unscrew both of these without pulling the water heater out. There is a LOT of crap between me and where they are.

Thanks in advance for any thoughts and ideas.

[JRTJH]

If it were me, I'd use a brass anti-flow valve with about 4 or 5 wraps of Teflon tape in the top and a brass adapter in the lower (cold water) port, also with 4 or 5 wraps of Teflon.

As for "anti-corrosion features on the aluminum tank and longevity" trust me when I say something else is likely going to go bad and force you to replace the water heater before a brass/aluminum corrosion issue at either of those ports will mandate tank replacement....

[mikec557]

Gary and JR

Thank you for your insights. I think I'll do a little preliminary research and see what it takes to remove and reinstall the water tank, just in case I can't do it all in the pass through.

Thanks again
Mike

[bobbecky]

If there is a concern about electrolysis between brass and aluminum, just use a stainless steel bushing instead of brass and you will not have a problem. Still use Teflon tape.

[GaryUT]

Originally Posted by JRTJH

If it were me, I'd use a brass anti-flow valve with about 4 or 5 wraps of Teflon tape in the top and a brass adapter in the lower (cold water) port, also with 4 or 5 wraps of Teflon.

As for "anti-corrosion features on the aluminum tank and longevity" trust me when I say something else is likely going to go bad and force you to replace the water heater before a brass/aluminum corrosion issue at either of those ports will mandate tank replacement....

My last trailer had brass fittings in the aluminum tank from the factory. The water heater lasted 11 years before a crack around the weld on the cold inlet started leaking. When I replaced it I tried nylon fittings, never could get them to quit leaking. Replaced them with brass fittings sealed with pipe dope like the original tank had. It was not leaking when we traded it in 4 years later.

Gary

[mikec557]

Thanks, I'll look into the stainless steel bushings but I think I can live with the brass. I picked up various parts at home depot today and ordered other parts from Amazon. I'm going to mod the (lower) cold water inlet to utilize a hand tighten connector like the hot water line at the top of the tank.

On a side note. We just finished up full timing a couple months ago. But last late Oct or early November we had an "intermittent" water pump cycling. I could never figure out why, except to think the pump was having issues. I think this may have been the cause of the pressure drop, causing the the pump to cycle for a few seconds to re-pressurize the line. I guess I should have been more diligent in my investigation...

[JRTJH]

If the water pump "cycles in the middle of the night" (and DW is sleeping) there's a leak or a diaphragm bleed back in the water system. It may not be easy to find, it may not cause a problem "this year" but if it's a leak, it will cause some damage if you ignore it long enough.

I'd suspect you're right, you've probably located the reason for your pump cycling...

[Frank G]

Just a thought, Do you use a water pressure regulator?

[mikec557]

Originally Posted by JRTJH

If the water pump "cycles in the middle of the night" (and DW is sleeping) there's a leak or a diaphragm bleed back in the water system. It may not be easy to find, it may not cause a problem "this year" but if it's a leak, it will cause some damage if you ignore it long enough.

I'd suspect you're right, you've probably located the reason for your pump cycling...

You're right about needing to find it, I was just unsuccessful. I thought it was probably under the coroplast somewhere because I checked all the plumbing lines with a dry paper towel and couldn't find anything. But I never thought to examine the back of the water heater. I'll get these two connections fixed up and see where we are with the water pump cycling.

[mikec557]

Originally Posted by Frank G

Just a thought, Do you use a water pressure regulator?

Hi Frank. Yes, ever since day one we have used a water pressure regulator. Started out, with our previous trailer, with the cheap one. Then later upgraded to an adjustable one with a gage.