Fresh tank won't stop filling

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NY_Dutch

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Ok, here's the update:
DId turn off the park water and used the coach water pump to do some dishes, take a shower, etc. Then installed the pressure control valve (Renator Water Pressure Regulator Valve), turned off the pump and turned on the park water. Wait for it... wait... wait... well ok, looks like no leaks. Hours later still dry.

I guess it can't be know exactly what the problem or cure was, but for now at least I'm relieved to back to normal. We have a scheduled visit in a few weeks with an RV Repair guy who has done a lot of stuff for us in Jackson, MS, On that "to do" list was looking at upgrading our current water pump. Looks like good timing.

Many thanks to all the helpful suggestions!
It was mostly likely just a bit of scale, etc, that was causing the internal check valve to leak back through. Running the pump dislodged it, and it may be trouble free for years to come. I recently replaced an original pump for a fellow in a 1982 TT. The only reason it was replaced was because the previous owner hadn't winterized it before the freezing weather hit here in the northeast and it cracked. I could have replaced just the head and used the original motor, but given it's age the current owner and I agreed a complete new pump was the best option.
 

Alontheway

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do not replace the water pump. The parts can be replaced very cheap, and if it has failed it just needs one part. At worst you can replace the water pump head (pumping part) and keep the motor.
When you take the pump apart you see a rubber flap with three holes it covers (on many pumps, not saying all are like this). That rubber flap is also preventing water from going backwards. I don't know how this fails other than it is cracked or crumbled.

A check valve would work to fix your current issue, but you need to fix the pump before more issues arise.

OR
It could be your bypass valve as mentioned above. Those are so simple not much will fail - usually an o-ring breaks and lets water leak through.
 

JayArr

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Replaceing it now gives you the added bonus of a spare part, stash the old working pump body in a corner under a bench or bed and forget it. If you ever need it in the middle of a trip you have it. It's nice to be able to fix something in a hour with parts on hand rather than re-arranging the following day to include a trip to the hardware store or nearest RC center for parts.
 

jymbee

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It was mostly likely just a bit of scale, etc, that was causing the internal check valve to leak back through. Running the pump dislodged it, and it may be trouble free for years to come.

"trouble free for years to come...", or in my case, days. :(

Disconnected the supply to wash the coach this morning and when I reconnected all and turned the water back on, water was again gushing out of the gravity fill. When I reconnected I did increase the pressure on the control valve from its former low setting of 25 to 40. Probably not a factor but worth mentioning.

Oh well, back to using the pump and will try from time to time to see if anything changes.
 

jymbee

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do not replace the water pump. The parts can be replaced very cheap, and if it has failed it just needs one part.
Logical advice and thanks but as I mentioned previously we had anticipated replacing the pump a few weeks from now to upgrade to higher capacity model.
 

Alontheway

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You did not tell us how fast the water is overflowing.

Water pipes are simple. It is either getting past your pump or past the check valve (is there one?) or past your by-pass or something is plumbed wrong (unlikely). No matter what it is you will have to take something apart, pull a panel or look closer at the pipes to work on it. This is not going to be just a matter of trickery to fix it.

The easiest way to plumb a system is a pipe goes from water tank to pump.
From pump to the camper.
The water is filled with a hose hooked up (I think in yours it is).
With the hose hooked up it feeds directly into the camper pipes after the pump.
There is a bypass valve anywhere in the pipes AFTER the pump (on the faucet side), when turned to ON this valve dumps water into a pipe that goes directly to the water tank.
The pump is a check valve (usually) so there might not be a check valve at all, or there could be one right after the pump. We cannot know this.
If water flows out fast then might not be going backwards thru the pump that fast, should be slow. If fast then, as mentioned by another post, could be your bypass valve is just not turning or somehow you are turning it past the closed and back to an open setting. Sometimes 90 degree turn is closed, but 180 deg turn is back to open again. We cannot know this without seeing it. If plastic it could be damaged and lets water through, could have an o-ring that is gone.

Your pump has a motor section and a head section. Look up the two and you might find other options for yourself.
 
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jymbee

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You did not tell us how fast the water is overflowing.

Water pipes are simple. It is either getting past your pump or past the check valve (is there one?) or past your by-pass or something is plumbed wrong (unlikely). No matter what it is you will have to take something apart, pull a panel or look closer at the pipes to work on it. This is not going to be just a matter of trickery to fix it.

The easiest way to plumb a system is a pipe goes from water tank to pump.
From pump to the camper.
The water is filled with a hose hooked up (I think in yours it is).
With the hose hooked up it feeds directly into the camper pipes after the pump.
There is a bypass valve anywhere in the pipes AFTER the pump (on the faucet side), when turned to ON this valve dumps water into a pipe that goes directly to the water tank.
The pump is a check valve (usually) so there might not be a check valve at all, or there could be one right after the pump. We cannot know this.
If water flows out fast then might not be going backwards thru the pump that fast, should be slow. If fast then, as mentioned by another post, could be your bypass valve is just not turning or somehow you are turning it past the closed and back to an open setting. Sometimes 90 degree turn is closed, but 180 deg turn is back to open again. We cannot know this without seeing it. If plastic it could be damaged and lets water through, could have an o-ring that is gone.

Your pump has a motor section and a head section. Look up the two and you might find other options for yourself.
As for "how fast" hard to say. When we notice water leaking out of the gravity fill on the other side of the coach we unscrew that cap and water GUSHES out as it's obviously been building up unnoticed for some time.

Pretty much ruled out the bypass valve not turning as it only turns 90 degrees and has been unchanged before and after the problem.

In any event, a new pump with greater capacity which is what we wanted before all this happened, is on order and will be installed in a couple of weeks. Just have to keep an eye on things in the meantime as even if it stops leaking for a time it's pretty clear that might well be only temporary.
 

Ex-Calif

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I reckon the 40 psi could be a factor. I'd go back to the lower setting...
 

Ex-Calif

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In context of a bad valve it could make a difference. He did say that it started leaking again when he increase the pressure.
 
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