Help! Fresh water tank overlowing

[Jason Worman]

Hi All,

My wife called and pics of fresh water tank overflowing while connected to city water, tank fill switch is off, water pump not running. It appears city water hook up is flowing right into fresh water tank, when I shut off city water, fresh water tank overflow stopped running. We had a new water heater installed a week ago and water pump, could this lead to any issues? Water heater is the new Dometic 10 gallon tank and water pump is a Shuflo.


Jason Worman

[Dan Johnson]

Could be the check valve on the water pump failed.

[Kemp B McLeod]

Could be the solenoid valve for the autofill. On mine it is in the same area as the pump. I shut the couch down while it was filling and it stuck on. I restarted the couch engine and it cycled to the off position. Hope it helps 

There should be 2 fill switches. 1 in wet bay and 1 in kitchen. I would check the both of them.

[Bryan Beamon]

Jason, it is probably one of 2 things. Your fill valve could be leaking allowing water to by pass when closed or your new water pump back flow valve is leaking. Try shutting off the outside water and running all your faucets at the same time for 20 seconds and then shut all faucets down. Turn your pump off and see if your tank over flow stops. Can you visually see your tank level ? If so mark the level on the tank so you can see if the water level is still rising.

[Jason Worman]

Hi Guys,

Thanks for the feedback. I shut off the city water, opened all the faucets, turned on the pump and basically emptied the tank. I shut off the pump and turned on the city water connection and have let it sit for several hours. I went back out to check and see if any more water filled it, there was some but not much. Will check it again in the morning. I called dealer where I bought the pump, because it had been two weeks I would have to file for warranty, ahip it back to manufacturer have them test  etc. Probably just as easy to replace via Amazon.

Will keep the post updated, the only weird thing is when the tank was overflowing, my wife was doing laundry.

Warmly,
Jason Worman

[Bryan Beamon]

Jason, you might have to insert a check valve before your water pump to stop the overflow  problem or we still don't know if your city fill valve is your problem. Keep us posted

[Jerry Carr]

Jason, be sure you shut off the water pump before the city water is turned on, if the city water pressure is on the low side the check valve may not seat. 

[David T. Richelderfer]

My guess is the tank fill valve is ON causing the water tank to overflow when filled.  Your tank fill valve may be electrically actuated or hand actuated - I don't know which.

On our coach, the tank fill valve is actuated electrically by toggle switches located at the water bay and kitchen sink. Our water fill valve does not shut OFF automatically when the water tank gets full.  Note - our kitchen sink toggle switch has been disconnected by a prior owner of the coach.

If the check valve on the water pump is defective, then the water pump would likely cycle intermittently with the city water shut OFF and with no open faucets in the coach.

I have read many threads here on the Forum citing faulty electric tank fill valves, called a Red Hat Valve.  Ours is located near the water pump.  Either open and clean it, repair it, or replace it.

[Jason Worman]

David,

I heard the Red Hat shut off, I'm wondering if something got stuck in it or it is worn out. I did do a warrant return on the water pump so will replace that as well as the water inlet valve as I heard those check valves can fail. Do you know of a substitute replacement for the Red Hat valve?

Jason

[David T. Richelderfer]

I do not know the inlet and outlet fittings' size on your Red Hat Valve but the link will show you some options for purchasing a new one.  You might be able to open the valve and clean it to prevent the need to purchase a new valve.  Pay attention to the valve's PSI rating if you purchase a new valve.  You will need a valve that, when closed, will remain closed under the water pump's maximum PSI.

https://www.google.com/search?q=red+hat+water+solenoid+valve&oq=red+hat+water+&aqs=chrome.1.69i57j0i512j0i22i30l3j0i390l4.21035j0j15&sourceid=chrome&ie=UTF-8