Water/plumbing problem

[munchie]

Need some help/suggestions for a fix to my water problem.

I have an 02 Journey DL. We fulltime and about 2 mos. ago I noticed that my fresh water tank was overflowing. I always keep my FW tank at 1/3 full and when last checked it was at that level. I was hooked to city water and my pressure reading was at 46psi according to my pressure gauge at the water inlet in my bay. I checked my valve and it was in the city position. I drained and using the city water inlet switched the valve to water tank fill position, filled - sanitized my system using the water pump and had great pressure with no burping of the pump. I completed the process leaving my normal 1/3 water in the FW tank. About five days later again on city water my FW tank was over flowing.
I turned the CW off and used the pump over several days to drain the tank. I kept my pump switch on 24/7 during this time. Again I had great pressure and no pump burping at any time. I also at one point drained my FW tank and using the CW inlet, left my valve turned to CW to check it. My normal fill time is about 25-35 min. Checking my level after 20 mins. my level light was still on empty. So, I eliminated the valve.

Help! Why is my tank filling up when the diverter valve is working?

[bdpreece]

Your water pump most probably has a bad back flow check valve that is allowing water to run backwards from the pump into the fresh water tank while hooked to city water.