Community Forums

Ken C · 10-02-2019, 04:13 PM

Sorry this is a little long, but it may help others from avoiding the same problem. After 18 years and 3 motorhomes, we recently allowed our fresh water tank to run dry for the first time. We had traveled and dry camped 1 night on the way to our destination using our tank and water pump. Apparently we did not turn the pump off when arriving at our full hook-up site for 10 days. We must have lost city water at some point and did not notice as the pump took over to supply water, but apparently emptied the tank prior to water being restored. Upon arriving at our next park, I noticed that the tank gauge read empty and added water to the tank. The pump would run, but no water pressure. I figured we lost prime, but could not get it to prime from the tank which was full. Tried several things including using the winterize function to prime from a container of water which did not work either. I finally tried filling the clear plastic winterize hose with water which worked. I suspect that the pump and/or water lines are positioned too high preventing the pump from priming. The odd think is that the pump would not try to run if we had city water pressure even though it lost prime.

GBRG07 · 10-02-2019, 04:57 PM

I have found if I don't turn the water pump off it will use water from tank instead of water hose.

Ken C · 10-02-2019, 06:00 PM

Quote:

Originally Posted by GBRG07

I have found if I don't turn the water pump off it will use water from tank instead of water hose.

Mine will only come on when we have city water and the pressure is lower than what the pump supplies

Old-Biscuit · 10-02-2019, 06:39 PM

Pumps have a pressure switch with a START set point and a STOP set point

City Water is normally at a higher pressure then pump Start Set point (which can be 30# or 40# depending on Model)

Pumps have hard time priming IF there is nothing open on discharge side to expel air & allow pump to prime

I use pump exclusively and have run dry many times
I also drain fresh water tank between trips.

TJ · 10-02-2019, 07:26 PM

Interesting! I routinely drain my water tank and refill it. Never had a problem with the pump picking up a prime. Maybe I'm just lucky.

TJ

NWIP · 10-02-2019, 07:54 PM

Interesting this post came up today. While on our way to Alamosa, CO we used enough water that pump was no longer supplying water. I knew I was low in the tank when we left a Grand Junction but didn’t think we would run pump dry.

On arrival in Alamosa it took some doing to get pump primed. I had faucets open, pump running with city water hooked up thinking this would prime pump but didn’t succeed. Water pump continued to run and was concerned about overheating. I ended up releasing both input and output on pump, reconnected and turned on pump with it coming up to pressure in 10-15 seconds. All is working fine now.

No city water hooked up, just using tank water as it will be in the mid 20’s tonight.

Rotten-Red · 10-02-2019, 08:04 PM

Ken C.

As pointed out by Old Biscuit "Pumps have hard time priming IF there is nothing open on discharge side to expel air & allow pump to prime".

When priming your pump always open a faucet or what I do is open the tank fill valve which takes the pressure off the pump and just recirculates the water back into the tank after the pump primes.

Finance · 10-02-2019, 08:09 PM

Something about the installation in our Ventana makes it hard to expel an airlock from the pump. Recently had to do the same as NWIP and disconnected the quick release at the pump to get it primed. We’ve run other rigs empty many times and this is the first one that seems to have this issue.