i have a 2016 catalina floor plan number is fs223. when i am connected to city water at the park, it fills my fresh water tank, where do i need to start to look for what is causing this too happen?
Common everyday question asked on every RV forum it seems. Yes, most likely the check valve in the electric pump.
1) remove city water hose. 2) run pump extensively cycling faucets on and off. 3) turn pump OFF 4) reconnect city water hose and DO NOT touch the pump switch with city water connected. 5) wait a while and see if your problem is cured. This process usually clears the check valve of debris and reseats the check valve.