What to Do About Air in Water Pump Lines

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When I use the water pump in my RV there is always air spitting out of the faucets and shower head. Why does this happen and how do I fix it? I checked and there are no water leaks. Could I need a new pump? Thanks in advance for any help.

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If you have air “spitting” on both hot and cold water, it usually means a crack or loose connection on the inlet or suction side of the pump. As it tries to draw water, air is pulled in. Sometimes the bouncing around a unit gets while going down the road gets air inside lines, however this is just a temporary condition and should stop after a little while.

Most of the time you can simply purge the lines by opening the farthest faucet until a solid stream comes out and work your way back.

If the spitting is just happening with hot water, then you have air bubbles in the water heater and should relieve the pressure valve and purge the water again. Good luck!

Safe travels,
David Solberg

RV Water Heater Troubleshooting Made Easy
Overview of RV Fresh Water System

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72 Responses to “What to Do About Air in Water Pump Lines”

  1. Sheila Guenther

    My water pump started staying on after using before stopping. Now it sounds weak and water flow is slow.

  2. Ray

    My thermostat keeps locking up on my 2004 Fleetwood Bounder 38n. I put a new thermostat on and it still keeps happening. When it does it one of my ac’s or Heaters will keep running but won’t cool or heat depending on which one. Can’t shut it off either. Take the thermostat off and unplug it and plug it back in and it works again. Happens about once a month. Could it be the controller and where would it be located if it is?

  3. Ray

    My thermostat keeps locking up

  4. Chris

    My dure flow water pump is drawing air at inlet hose. It will pump fine hose connected "no incoming water from city source". As soon as disconnect hose pump loses pressure.

  5. Terry Brandon

    My fresh water tank is filling up while I am hooked up to city water. My research indicates that my water pump check valve is not closing properly and allowing water to flow into the fresh water tank. Are all water pumps universal fit, I have found one at Campers World with 4 gpm and woul like to purchase prior to removing the old / defective pump. But would like to be confident that the new will fit. Also, I cannot find any video on replacing my water pump. Any help or suggestions on either of these issues would be greatly appreciated. Great Question! Please log into your account and click on “Contact Us” at the bottom of the page. We need more information on the make/model of your RV. Once you sugmit that information it takes 2-3 business days for our Experts to answer your question. Thank you!

  6. Greg Patterson

    My thermostat is not working correctly. I need to set it at 52 degrees to get my air conditioner to keep the temperature in my Motorhome at 74. Similarly with the furnace. I tried replacing the thermostat but that was not the problem. I purchased a relay box and am ready to replace the existing one but am concerned because there are 2 blue wires and 2 red wires as well as a red and black on the control side. How do I determine where each wire should be connected.

  7. Daniel LaChappelle

    When hooked up to water source I only get a little bit of water then it quickly tapers of an stops

  8. Anna brophy

    What would cause water to fill up in my floor heater vents? I have cleaned it up and again there is close to an inch of water in there and I can’t find the source. Thank you Anna

  9. Terry Voss

    Spitting water pressure, replaced the water pump, same problem. No water leaks. Connections seem tight.

  10. Albert

    Help please I've been broken down here for 2 weeks. Original problem a radiator hose came loose, lost appt of water. I tried making it back to my spot which was 2min away. To no avail. So let it cool down bought antifreeze coolant filled it. And still wouldn't start. Was cranking but not starting. Put fuel in carb and would start. Friend of mine says it's my fuel sending unit. Which he doesn't hear turn on. So I replaced the fuel sending unit. By the way, in trying to fix problem friend kept pouring gas in carb and one time it was going to turn off and pushed the gas and "boom" it caught fire! We were freaking out trying to turn it off but wouldn cause... obviously all the gasoline. But finally we turned it off. From what I examined there was no really damage done a few wires which I replaced. And after I tried to start and it would crank but wouldn't start. Same problem. Anyhow I replaced sending unit, which took me 2 days, as to no friends or help. Anyhow, replaced it. And replaced 1 battery cause was dead and no good. So now I try and start and it barely cranks now and can't even try to start. I did notice "1" plug wire burnt and it cracked off. I went and bought a cheap wire from auto zone and replaced it. Can that be the problem. Cause my "2" batteries that I have in my rv show a 12.9 volt reading which usually would start my rv??