New water pump constantly runs

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Malibu39

Malibu39

Active member
Joined
Jun 5, 2017
Posts
41
Location
Medford Oregon
Hi there,

Just bought a new to me 2004 Itasca Horizon 40' Class A. I am a long time RVer but this is my first diesel Class A. It's simply awesome, what a game changer, but having problems with the water system.

- Water pump does not shut off and the pressure is low
- I discovered the pump is brand new when I went to check it out
- It will only pump water when the switch is on "City Water" instead of "Water tank Fill"
- When its on "water tank fill" the pump just runs with no water coming out of the faucet at all. I assume that is normal
- When hooked up to city water, everything works great
- It does not appear to be filling the fresh water tank when I am hooked up to city water, and flip the switch to "Water tank fill". I can fill it by putting a hose in the regular water fill on the other side.
- Obviously no water leaks anywhere

I've read a lot of posts about leaks, antifreeze lines, etc.  But I cannot check the unit until this weekend as it is parked at the lake. Wondering if these symptoms look like its something easy.

Thank you!
 
Look for a electrical switch to shut the pump off.
Do you have water in your fresh water tank? If you don't then pump will just run.
Make sure the Fill VALVE, not switch, is closed. Turn it clockwise until it stops. Usually it's only 1/4 turn. .
 
Oh yes, I can manually shut the pump off of course, just a pain to do that every time I want to use water. I forgot about it and left for the day and it about drained my batteries.

There is water in the tank, yes.

And the fill valve is in fact closed, its on "city water".

I assume I have an air leak somewhere.
 
Not sure if this is just a Winnie anomaly, but they could do a better job labeling the water valve switch.
"Water tank fill" means just that. Once your tank is filled, you need to switch to "city water" even though you're not hooked up to city water.
On mine, the water pump runs if there is air in the lines. Running the toilet seems to clear it up.
 
So if the pump is good and there are no water leaks, it has to be sucking air between the pump and the water tank, correct?
 
- It will only pump water when the switch is on "City Water" instead of "Water tank Fill"
- When its on "water tank fill" the pump just runs with no water coming out of the faucet at all. I assume that is normal
Click to expand...
Yes, both of those are "normal" (working as designed).  In the Fill position, water in the lines runs back into the tank so the pump would just pump water from the tank right back into it and never stop.

Leaky city fill valves seem to be a common problem in Winnebagos. Apparently the valve doesn't always close completely when set to City and some water flows to the tank. When using the City hook-up the tank slowly fills and eventually overflows. When usiong the pump, the pumps runs either intermittently or continuous, depending on the amount of leakage.
 
Got it, thanks, I will check that valve next. I have been hooked up to city water for long periods of time and did not notice any water going into the fresh water tank, or even hearing it.  But when I activate the water pump, I do hear water moving around, so its probably the city water / tank fill valve.  Great tip.
 
Malibu39 said:
- It will only pump water when the switch is on "City Water" instead of "Water tank Fill"
Click to expand...

Malibu39
If you turn the water selector valve FROM of "Water tank Fill" TO "City Water" me thinks you will solve the problem.
My 12V water pump runs continuously and pumps no water into RV water system if/when I accidentally leave the water selector valve on "Fill Tank".

My selector valve has these 2 positions.
One labeled FILL TANK... the other CITY WATER/RUN PUMP.
 
Oh yes, it is only in the "city water" position, never in the "fill tank" position.  And it still constantly runs, but like another fella suggested, those switches commonly go out on the Winnebago line.  So that is the first place I am looking.
 
Malibu39 said:
Oh yes, it is only in the "city water" position, never in the "fill tank" position.  And it still constantly runs, but like another fella suggested, those switches commonly go out on the Winnebago line.  So that is the first place I am looking.
Click to expand...

The correct name is valve not switch.  A switch is something electrical.
 
It is also possible the pump is air bound.  Make sure you have adequate water in the tank and turn the pump on.  Then start opening faucets until water starts coming out.  Let the water run a while and the air should purge out of the system.  As BinaryBob stated, run the toilet also.
A loose suction line on the pump could also be a reason for the constant running. 
Is your water heater full?  If not then the pump will run for a while until the heater fills up.
 
The pump may also run constantly if there is either a blockage in the pump inlet (from the tank) or an air leak there. In either case, the pump cannot get enough water to build pressure. However, with a hose connected to the city inlet, city water pressure is usually high enough so that the pump switches off anyway. It takes about 45 psi for the pump to shut off, which most city system have (with no faucets open).
 
Hi, I read all the answers you got and they confused me.  So let me see if I have any idea what the problem is.  The pump is only used when city water is not connected.  The on board fresh water tank must have water, 'enough to pump' in it.  It does not matter how you put the water in, I like to use the city connection and turn the valve to fill, make sure the water is turned on at the ground faucet, caution, it will overflow the tank and flow out at the normal fill inlet.  after you get some water in the tank turn the pump on and see I it pumps water at the bathroom sink faucet. close all the faucets and see if will pressurize the lines.  If it does it is working normally.. On a new pump there may be a small white plastic thing on the
line that I can't see any use for, maybe it is a noise abater or pressure equalizer,  mine stopped the pump from working so it is in the trash. It kinda looks like a tiny plastic umbrella, about two inches across. You can unscrew the line and connect it to the pump.  hope this helps,  [email protected]
 
BinaryBob said:
Not sure if this is just a Winnie anomaly, but they could do a better job labeling the water valve switch.
"Water tank fill" means just that. Once your tank is filled, you need to switch to "city water" even though you're not hooked up to city water.
On mine, the water pump runs if there is air in the lines. Running the toilet seems to clear it up.
Click to expand...
I agree. I have a 2004 winnie sightseer and this drove me insane dewinterizing this year. My pump was doing the same thing. I had the switch on water tank fill. Was trying every valve I could turn and still pump just stayed on. I thought I broke something. I got frustrated and just turned the switch to city water and everything works fine. Drove me crazy and as Bob say's it's just a stupid labeling issue.
 
charles king said:
The pump is only used when city water is not connected.
Click to expand...
Correct. When you are using city water the pressure from the city water is enough for the motorhome. You might want to by a regulator so the pressure is not too high from an external source. Most RV parks don't have high pressure as they understand the issue it could cause (plumbing cab break). But if you hook up to your house or some other place you can get some high pressure. I used to own a window cleaning company and have seen pressure come from buildings over 150 psi.
 
Try adjusting the the set screw on the front of the pump. If it's adjusted too high the pump won't shut off. At least that's what worked for me.
 
Sorry for the mis-read. If you are trying to fill the tank with the hose screwed into the city water and then turning the valve to water fill and it does not fill the tank. It's most likely the valve. With mine you can look directly under the system and see the connection. It's very simple, the valve just diverts the water into the holding tank. The non-screw hole is really only if you are in a place that does not have an option for such a thing IE you run over your hose and bend the end or have to cut it off. Mine does fill the tank when I turn the valve to water fill and I'm screwed in. Now with that said my pump will not operate correctly IE provide water to the motor home unless I turn the valve back to city water. It will just stay on like yours does until I turn it back, then it works as you would expect. I am going to presume it's the valve not directing the water into the fill tank.
From my manual.
"Always keep the tank fill valve closed unless you are filling the tank. If this valve is open while using the city water, the water will keep flowing into the tank and out the tank vent tube."
 
Update: So unable to find any leak whatsoever on the RV (it only took me 15 hours so no biggie) I decided to plug the outflow just to make sure it would shut off.  It didn't.  So its a problem with the brand new pump.

Its either the bypass valve adjustment or just a bad pump.  Apparently if they are out of adjustment, the pump will just constantly run.  Fabulous. There are two Allen screw adjustments on the pump.  Although the manual is extremely limited, I have found some other stuff online on how to adjust. Hoping to continue the troubleshooting process this weekend, prior to buying a new pump.

Has anyone had to mess with the adjustment on their water pump?
 
You must log in or register to reply here.

Latest posts

Members online

Total: 1,191 (members: 27, guests: 1,164)

Forum statistics

Threads
131,931
Posts
1,387,721
Members
137,682
Latest member
duckyw7528
Back
Top Bottom