Water pump air lock?

[TY PECK]

I am in a 2012 Interstate. If I run the fresh water tank too low and then refill there seems to be an air lock in the pump. Twice I hooked up to city water and the pump cleared itself and begin working after I disconnected the city line. The last time I tried, this did not work. How do you reprime the pump?

[dznf0g]

Shouldn't happen unless there is something wrong with the pump, or more likely a leak on the suction side of the plumbing allowing the pump to suck air.

[A W Warn]

I have had that happen to me a few times over the years. Most times it has been the quick disconnect at the in-line filter right beside the pump's intake, where you take it apart to clean the screen. Check to see if it has come loose. Once I had a stress crack in the pump head housing that was letting air in on the intake side of the pump. Hope you do not have that problem!

[Inland RV Center, In]

Originally Posted by TY PECK

I am in a 2012 Interstate. If I run the fresh water tank too low and then refill there seems to be an air lock in the pump. Twice I hooked up to city water and the pump cleared itself and begin working after I disconnected the city line. The last time I tried, this did not work. How do you reprime the pump?

The input (suction) side of the pump has a small air leak.

Tighten all the fittings and the problem should go away.

Andy

[TG Twinkie]

Disconnect the discharge hose from the pump. Turn on the pump. You should see water come out the discharge. Turn off the pump, reconnect the discharge hose. You should be good to go. Open a faucet and run the pump to test. Close the faucet and the pump should run for a few seconds then stop.

[handn]

Originally Posted by dznf0g

Shouldn't happen unless there is something wrong with the pump, or more likely a leak on the suction side of the plumbing allowing the pump to suck air.

X2, Pump will purge itself unless there is a malfunction.
The place to start is at the pump. Mine lives under the wardrobe closet on the street side. The cabinet where the pump lives is hinged and pops open.
Examine the pump and fittings. Fittings should be finger tight. If one is loose, you have likely found the problem. The pumps don't last forever. Six years is old with moderate use.
You can buy a kit from Sureflow and replace the head or diaphram only for about half the cost of a new pump.

[bolerama]

I've had that issue a few times. To prime the pump, I remove the outside shower head and suck on the hose with the cold water tap turned on. That is usually enough to get the pump primed. I know it sounds crude, but it works..

Paul

[TY PECK]

Thanks for all the advice, tightened connections and did the shower hose tip and it is working.

[Inland RV Center, In]

Originally Posted by TY PECK

Thanks for all the advice, tightened connections and did the shower hose tip and it is working.

Goes to prove that many times, a seemingly difficult problem, can have a so very simple fix.

Andy

[HowieE]

In order to loose prime you would have to have run the fresh water tank dry. Now say that did happen the pump should pick up a prime if you have put water in the fresh water tank and with the pump on open any faucet to remove the pressure on the output side of the pump.

If the pump will not pick up a prime at this point you have a leak on the suction side between the pump and the tank. Not likely if the system has been working.

[TBRich]

Every once in a while we get a air in our water system that results in a knocking of the water pipes near the rear of the rig. It seems to get "caught" in the high point of the system, which is the shower hose. I don't think it's from a bad pump seal. It seems to happen only after we've been connected to city water. I attribute it to connecting to city water and having some air forced through the system ahead of the city water flow. We've had success remedying it by putting the shower sprayer head on the shower floor and running water through it for a bit...it seems to clear the system every time.