Faulty or dirty check valve in the water pump will let city water flow backwards through the pump.
Try burping it by shutting off city water. Turn on the pump and open s cold water faucet for 10-30 seconds until the pump runs. Then turn the faucet off. Do this a couple times. Then shut the pump back off, and then try turning city water back on. If water comes out again, that means the pump check valve inside the pump is messed up still.
At that point, Iíd run off the pump and fresh tank until you can pull out the pump and see if you can repair it or have to replace it. Common problem. Can sometimes be prevented by ALWAYS using a fine particle filter on the city water hose when hooked up or filling the fresh water tank.
Search the forums for lots of threads on this issue. Itís not uncommon.
Rich, KE4GNK/AE, Overkill Engineering Dept.
'The Silver HamShack' ('07 International 22FB CCD 75th Anniversary)
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