This year when I winterized the motorhome, I goofed and forgot that the water pump was on and hit the check valve on the city water inlet on the outside. Had to replace the city water inlet due to the...
IF your water pump has the in line filter between the Tank and the pump,(it is mounted on the inlet side of the pump), odds are the plastic housing cracked. If so, just replace the filter. To test, remove the Filter and connect the feed line directly to the pump. Doug