Dear Dave,
OK, Dave, I’m stumped! Despite having continual strong water pressure using my fresh water tank, my RV’s water pump refuses to shut off. I’ve searched high and low for any leaks and cannot locate any, inside or underneath the unit. I did use the water pump recently while connected to city water. Perhaps this has disrupted the pump’s control valve? If so, how do I fix it? Thanks. —Karl, 2019 Gulfstream BT Cruiser 5230B
Dear Karl,
It doesn’t necessarily need to be a water leak—it could be an air leak. Your water pump most likely is a Shurflo on-demand pump that draws water from the fresh water tank and provides pressurized water throughout the rig. It has a pressure switch in the head which is designed to sense when the faucets are turned off and build up pressure in the lines and shut off the pump. It is possible this pressure switch is bad and there is no actual leak. That is why I would pull the pump out and bench test it, if possible.
We had a 2003 Winnebago Brave that had a cycling problem and the owner was adamant it was the pump. I pulled it out and hooked up a draw tube to the inlet side that went into a 5-gallon bucket of water. Hooked up a 12-volt battery and capped off the outlet side. It did not cycle for the entire day, so I know it was not the pump.
If you have access to the pump, you can test this by removing the outlet side pipe and cap off the fitting. It should be 1/2 inch, and you can get a cap at any home improvement store.
More possible reasons for water pump running
If the pump builds up pressure and stops, then you will know it is a leak in the outlet side. This could be a shower head that drips down the wall into the drain that you can’t see, or the toilet letting water bypass. If it still keeps running, then check the filter on the inlet side, as the plastic bowl can have a slight crack and air gets in.
If all that is good, I would remove the pressure switch on the front and clean it or replace it. Some have an adjustment screw on the pump head, so check your owner’s manual to see if that needs to be adjusted.
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My RV’s water pump “cycles” when not in use; dealer says this is normal. Really?
Dear Dave,
My RV’s water pump will kick on for about two seconds once or twice a day when no water is being used. The service repair folks said that was normal. This did not occur in my other RV. Should I be concerned about a slow leak, or is this truly normal? Thank you for your assistance and time. —Cathy, 2023 Chateau 27R
Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”
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Turn the city/fresh water valve to city fill when using the fresh tank that will fix your problem. It closes the air leak.
It is probably an Artis pump .. Similar to Shurflo and widely used in marine as well as RV applications. Research would have shown this and possibly affected the diagnosis.
I just took my new 2013 Freedom Express 20SE for its shake-down cruise, and the water pump was cycling. Checked “everything” before I noticed that the water heater was dripping from the drain hole. The nylon stopper wasn’t tight.
We are so happy with our dealer, we have bought 4 units from them, and have never gotten the “that’s normal” reply when it goes in for a problem. They seem to actually listen to what the customer is saying.