[DutchmenSport]

To figure out if you have a leak or if it's just the pressure relief valve, put water in your fresh water tank and disconnect from shore water hook-ups. Now, turn your water pump on and let it pressurize. If there is a leak, you'll hear the water pump cycle on and off, pretty fast. If it does not cycle on and off, but stays off, you have no leak. The water is coming from somewhere else. Or else the pressure from your shore water connection is too much, blowing something out, that doesn't happen when the water system is under a lesser pressure with the water pump only.

It's an easy first level of research to define the root cause of your problem. This is probably the main reason why I never keep connected to shore water, but pump from my fresh water tank always. It takes only about 2 ounces of water to run and the water pump turns on. When the pump turns on and no faucets are on, it gets my attention .... always! Good case in point is the automatic ice maker in the refrigerator. And just last week, the wife did not turn the knob completely off on our toilet Bidet and it was slightly running. I heard the water pump cycle on and off. Found the toilet Bidet running and good I did, otherwise it would have filled the toilet bowl and eventually over flooded on the floor. I've caught faucets not turned off completely, leaking water at the anode rode/ drain on the water heater, and my outside shower faucets turned on, but the head of the shower button was off (still allowing it to drip a little). If I were hooked up to shore water, I would have never known these drips and leaks were going on. The water pump cycling on and and off is an immediate attention getter. Plus, it helps us be keenly aware of how much water we are using so it help to let us know when it's time to dump the sewer holding tanks.