Can't fill the water tank.

Topic: Can't fill the water tank. (Read 1170 times) previous topic - next topic

Can't fill the water tank.

October 15, 2018, 02:25:37 pm

I have filled the tank in the past with no problems.
While preparing to leave for a trip on Friday, I emptied the fresh water tank and attempted to fill it with fresh water. City water is flowing through the faucets, but when I opened the valve under the bathroom sink, no water will flow into the tank.
I exercised the valve thinking there may be a blockage, but to no avail. The valve turns smoothly, but no water is flowing into the tank!
Is it time to replace the valve, or could there be another gremlin?

Thanks in advance for your assistance.

Re: Can't fill the water tank.

Reply #1 – October 15, 2018, 03:09:51 pm

Quote from: Want2rv – October 15, 2018, 02:25:37 pm

Is it time to replace the valve, or could there be another gremlin?

Sure sounds like the valve has went bad. Do you know if the valve is a gate, globe, or ball style valve? I have seen all three in that location. If I was to replace it personally I would go with a ball valve, this is kind of like boxers or briefs as to what will work best for you.

Mike

Re: Can't fill the water tank.

Reply #2 – October 15, 2018, 04:03:42 pm

Try opening the valve a bit at a time as you may have gone past the open part. I know this all sounds screwy but I had this same problem on our 93gv with under cabinet valve and carefully opening the valve this way made it work.
JohnH

Re: Can't fill the water tank.

Reply #3 – October 15, 2018, 04:28:19 pm

John, I cracked the valve slowly as you suggested, but no water flow! One of these days I'll get lucky and the easy fix will work! Thanks for the suggestion.

Mike, I have accessed the valve and will replace it with the Shark Bite ball valve I just purchased. Hope this works! Thanks!!!

Re: Can't fill the water tank.

Reply #4 – October 15, 2018, 05:19:57 pm

I just pulled the old valve out and it is opening and closing as it should. There is no water reaching it.

The line to the valve is teed off a water line and the line out feeds down to the bottom of the tank. There is city water pressure at the sinks and toilet. Wouldn't the line it is teed from cary the city water? I don't get it!

If I had the time before my trip, I would install a gravity fill.

Re: Can't fill the water tank.

Reply #5 – October 15, 2018, 05:33:38 pm

Pinched pex or frozen? Another valve somewhere that might of got bumped closed. It worked before.

Re: Can't fill the water tank.

Reply #6 – October 15, 2018, 06:24:32 pm

If your backflow check valve has failed some of those parts could be lodged in the "T" that feeds water to the fill valve.

Mike

Re: Can't fill the water tank.

Reply #7 – October 15, 2018, 06:27:25 pm

If you still have the valve removed, you might try blowing some (gentle) air pressure through the pipes in both directions. Could possibly dislodge whatever is plugging up the water pipe, or at least give you a clue where to look.

Re: Can't fill the water tank.

Reply #8 – October 15, 2018, 08:45:24 pm

I like the suggestion to blow air into the lines. I'll try it tomorrow.

Any idea where the backflow check valve is located?

Re: Can't fill the water tank.

Reply #9 – October 15, 2018, 08:54:18 pm

Quote from: Want2rv – October 15, 2018, 08:45:24 pm

Any idea where the backflow check valve is located?

On your coach it should be built into the back of the fitting where your shore water hose hooks to. This is a complete assembly both hose hook up and check valve. If broken just replace as they aren't fixable.

If you have a hose reel then it should be right where the hose reel connects to the coach water piping.

Mike

Re: Can't fill the water tank.

Reply #10 – October 15, 2018, 11:53:30 pm

We had our backflow preventor valve go (2nd one is less than a year) so I just used a garden hose shutoff valve on the hose end where it would normally plug in to the backflow preventor. Works great and a whole lot cheaper and easier to install!

Re: Can't fill the water tank.

Reply #11 – October 16, 2018, 09:12:52 am

We had continuous "dribble" out of our fresh water fill hose. Tried cleaning out the backflow preventer - failed. Installed a manual shutoff valve in the water fill pipe and removed the guts from the backflow preventer - problem solved.

You can see the white plastic push-on valve directly above the water hose reel:

Re: Can't fill the water tank.

Reply #12 – October 16, 2018, 10:48:02 am

Well....I removed the backflow preventer and verified that it was working properly. While disconnected, I blew compressed air through the water line at the valve under the sink. Some air would pass through the line.

I installed the valve expecting the system to work!!! It did not!!!

No water is going into the tank but the city water does work.

Not sure what to do next. Wish I had a diagram of the water system!

Re: Can't fill the water tank.

Reply #13 – October 16, 2018, 11:09:19 am

Quote from: Want2rv – October 16, 2018, 10:48:02 am

Not sure what to do next. Wish I had a diagram of the water system!

This is very puzzling, to be sure. Diagrams of the coach water system are very hard to find, if indeed they even exist.

Since you have filled the tank successfully in the past, but it doesn't work now, it MUST be some sort of recent blockage in one of the pipes.

I am straining my brain, trying to imagine some scenario that would explain the symptoms you describe, but so far I got nothing!

Sorry!

Re: Can't fill the water tank.

Reply #14 – October 16, 2018, 11:18:40 am

I had the same problem last fall while at Georgetown/Jim Hogg CG. I tried everything I could think of and then I unhooked the water line right before it goes into the fresh water tank, at the shutoff valve. I then hooked up the air compressor and blew air back thru the line. Air didn't do it so I back flushed using our water hose. Hooked up the tank and have had no problems with water system other than mineral deposits plugging the faucet screens. This cleared up almost immediately. I also ended up putting a ball shutoff valve to replace the rubber one on the tank fill line because the original valve leaked water into the tank until it overflowed.
I put in a new backflow preventor that failed just last month so...garden hose shutoff valve now works great!!

Re: Can't fill the water tank.

Reply #15 – October 16, 2018, 11:25:31 am

Quote from: Want2rv – October 16, 2018, 10:48:02 am

Well....I removed the backflow preventer and verified that it was working properly. While disconnected, I blew compressed air through the water line at the valve under the sink. Some air would pass through the line.

I installed the valve expecting the system to work!!! It did not!!!

No water is going into the tank but the city water does work.

Not sure what to do next. Wish I had a diagram of the water system!

You say that some air does pass through the line. Is that in both directions? Can someone outside confirm that it's flowing out through the water fill fitting AND into the tank when blowing through either side of the valve piping? It has to be blocked on at least 1 side.

If some air is passing through in both directions, then water may also be passing through but too slowly for you to notice quickly in the tank. Do you have a clear sediment filter or hose that you can "see" water flowing through, or not?

Re: Can't fill the water tank.

Reply #16 – October 16, 2018, 01:00:08 pm

I don't have an assistant at this time to verify the air flow.

The input on the bottom of the tank is accessible, it tees off to the water pump input. Looks like it's time for a Home Depot run to get some plumbing materials! I like Nighthawk's idea to backwash the entire system!

Thanks!

Re: Can't fill the water tank.

Reply #17 – October 16, 2018, 01:10:25 pm

With the backflow preventor off I duct taped an old sock on the end before flushing from the tank end, just to see if anything came out. Got lots of mineral flakes from when I "cooked" out the system two or three months earlier at home using 5% vinegar.
I used water to back flush the system because air is compressible and water not so much.

Re: Can't fill the water tank.

Reply #18 – October 16, 2018, 01:16:23 pm

I have no shortage of old socks!!!

Re: Can't fill the water tank.

Reply #19 – October 16, 2018, 01:40:44 pm

Barry Beam made up a great site with all sorts of info on our coaches. Here is the link to the info on the water system.

Technical Help - PLUMBING

Are you sure that the water fill solenoid valve (if you have it on your coach) is working? Operate the fill switch while someone listens to it opening.

Keith

Re: Can't fill the water tank.

Reply #20 – October 16, 2018, 05:38:00 pm

Keith, my Foretravel has a manual valve under the bathroom sink.

Thanks for the link.

I'm probably going to install a gravity fill on the tank. I ordered a Uniseal that will be delivered tomorrow. After searching this forum, I see that others have done so and it seems like a straight forward job.

This forum is awesome!!!!

Re: Can't fill the water tank.

Reply #21 – October 17, 2018, 08:57:15 pm

I got tired of chasing gremlins!

I used the Uniseal I ordered 2 days ago as a fail safe!

It took less than 30 minutes and 30 dollars to install a gravity feed to the tank!

25 minutes to fill the tank and all is good!!!

Thanks all for the assistance!

Affiliate Notice