Bad Check Valve in Pump???
Searched but didn't find anything similar so throwing this out there. Put in some new Pex plumbing and had the following situation on the initial pressure check.
Hooked up to city water for the test, the lines filled and had pressure but the water tank was filling at the same time. The pump was hooked up as normally but at present I have no power in the trailer so can't turn it on at this point. Drained the lines, disconnected the pump line that pulls water from the tank and capped off that side of the pump. Tried again and the lines pressurized as normal with no more flow to tank. Nothing new added in this area, just upgraded original drain valves for hot, cold lines and water tank to ball valves. All this follows a complete subfloor replacement so the pump has been stored for awhile.
I pulled the front off the pump and that all looks good. No trash, has a filter on the side, it's clear. Found several parts breakdowns of the pump online but none of them show where the check valve is located. All say " check valve not shown". It's a Shurflo Model # 2088-422-444.
Can someone point me to the location of the check valve in this pump?