Colin Blamire
New Member
Hi,
Installed a new sewage pump in my pit. 2" ABS, straight vertical rise 8', a 90 deg bend with a 5'run, then another 90 deg bend to straight sloped run of 50' to the septic.
A foot above the pit lid I installed a sewage rated flapper check valve vertically with flow correct. Seems all good.
Discharge goes well, but then backflow runs through the check valve back into the pit. Seems there is a lot of negative pressure running back to the pump.
I've tried 2 weeping holes on the pipe between the thread and check valve, one below the water line and then one above. I've covered each separately, and then both. Each time I remove the check valve to check for debris there is none...and the valve works for one time only after I replace it. I've also tried 2 different check valves to rule out damage. Is this an air flow issue? I've tried so many times the water in the pit is probably drinkable. What coul be keeping the flapper from closing?
Any ideas?
Colin
Installed a new sewage pump in my pit. 2" ABS, straight vertical rise 8', a 90 deg bend with a 5'run, then another 90 deg bend to straight sloped run of 50' to the septic.
A foot above the pit lid I installed a sewage rated flapper check valve vertically with flow correct. Seems all good.
Discharge goes well, but then backflow runs through the check valve back into the pit. Seems there is a lot of negative pressure running back to the pump.
I've tried 2 weeping holes on the pipe between the thread and check valve, one below the water line and then one above. I've covered each separately, and then both. Each time I remove the check valve to check for debris there is none...and the valve works for one time only after I replace it. I've also tried 2 different check valves to rule out damage. Is this an air flow issue? I've tried so many times the water in the pit is probably drinkable. What coul be keeping the flapper from closing?
Any ideas?
Colin