Pressure Relief Valve

[Fender]

Hi folks, I'm wondering how common it is to have a bad pressure relief valve?
We're talking a June 2022 trailer and this is the first trip out since winterizing last fall.
We're not talking a slow drip here, water gushing out as if the valve is wide open, although I'm not sure what would have caused the valve to open in the first place. Sticking closed would seem a more likely occurrence.

I, of course, tried opening and closing the valve a few times thinking something is sticking but didn't help.
Am I missing something here?

[Iowa Dave]

Is your problem with the fresh water hookup when hooked up to “city” Water or when you’re filling your fresh water tank with a hose from a water source. Once the fresh tank is full excess water will gush from the relief hole near the tank filler hole till you shut the water source off. Otherwise I think it’s fairly rare for the city water backflow preventer to fail. Just not sure where your problem is occurring.
Maybe a picture would help?
Iowa Dave

[Fender]

Originally Posted by Iowa Dave

Is your problem with the fresh water hookup when hooked up to “city” Water or when you’re filling your fresh water tank with a hose from a water source. Once the fresh tank is full excess water will gush from the relief hole near the tank filler hole till you shut the water source off. Otherwise I think it’s fairly rare for the city water backflow preventer to fail. Just not sure where your problem is occurring.
Maybe a picture would help?
Iowa Dave

Hi. Sorry, I probably didn't give a great description.
Problem is the hot water heater pressure relief valve. I'm hooked up to city water and wanted to turn on the hot water heater.
I recalled that I had not reset the valves used to bypass the water heater when winterizing so reset those to enable the water heater to fill.
Once the water heater filled water started gushing out of the relief valve. I tried a few times opening and closing the valve thinking it must be stuck open but no change.
I could take a photo later but I think all it will show is water shooting out of the PRV!

[Iowa Dave]

Oh ok. Yes they do fail on occasion. The solution as I’ve seen it is to replace the valve and use Teflon tape ( about three wraps) on the threads.

I was camped with some friends who had a motor home. The valve would not close or quit leaking when it finally made temperature. We tried twisting the flipper back and forth a few times and then snapping it back down flush with the valve top. Didn’t help. So we went to a small town true value hardware and for an new one and installed it. Worked fine after that.

I think he used a crowfoot wrench kit to get at the flats on the valve and turn it out. It’s tight in there. He was one of my park maintenance foremen before we retired and could repair about anything.
Iowa Dave

[Ron in BC]

Originally Posted by Fender

I, of course, tried opening and closing the valve a few times thinking something is sticking but didn't help.
Am I missing something here?

If you remove some PRVs you'll see that they usually have some corrosion, and for lack of a better word, crud inside.

I cringe when I see folks mention that they opened their PRVs for one reason or another. If a piece of crud gets on the valve seat the PRV will leak.

Ron

[Fender]

Yes, looks like a trip to the hardware store for me!

[Iowa Dave]

Probably wouldn’t hurt to spray some wrench eze on the threads and wait a little before you try to back the old one out.
Iowa Dave

[Fender]

Originally Posted by Iowa Dave

Probably wouldn’t hurt to spray some wrench eze on the threads and wait a little before you try to back the old one out.
Iowa Dave

In looking at it I was thinking the same thing!