I'm camping and hooked up to city water. My fresh water tank is getting water in it some how. Is there a check valve that could be bad that is causing water to bypass and get to the fresh water tank. It is very slow whatever it is. It's taken 3 day for 2/3 of a tank to fill up.
Yes there is and it probably has some dirt or debris in it. Best easy potential fix is to disconnect from city water. Use the pump and pump some of it through the system to try to clean up the check valve.