Troubleshooting RV Water Pump that was Ran Dry And Now Has Low Water Pressure

Updated 04/22/2020 | Published 04/21/2020

Question:

We have a flow-Max water pump installed in our food truck under our three compartment sink. I let the water get low one day but turned it off immediately when I realized what I had done. According to the information on this pump even if it runs dry it wont cause damage. So now there is no water pressure. The water comes out super slow and our hot water heater wont kick on. We have a tankless hot water heater. Can you tell me what I should do? Purchase aother pump, or possibly replace something? Thank you for your time,

asked by: Robin A

Expert Reply:

Sounds like your water pump lost it's prime since you ran it dry. I can help you try priming the system with the steps below. If that doesn't help you may have a blockage or need a new pump.

Fill up your fresh water tank.

Turn on the cold water in your RV and make sure the faucets are completely open.

Switch on the water pump near your RV water tank.

This should prime the pump by pushing water up from the tank through your faucet. Let the water flow a while, then turn the faucets off. Each and every faucet needs to be purged of air, so you may want to open and close and run water to the faucets one at a time. (Don’t forget other water outlets like your showerhead and RV toilet!) Your pump will be fully primed when the water pump only turns on when a faucet is actually open. (Not in between.)

expert reply by: Jameson C