Zoeller WM266 waste discharge pump
I have a recently replaced Zoeller WM-266 waste discharge pump for a Qwik Jon system in my basement. The pump continues to hum (usually at night when I'm not using the water in the basement) It makes this noise for as long as four minutes before it engages or out of frustration I will turn the basement faucet on to expedite the process.
The times I had the plumber come by to check the system, I could not duplicate the problem. However he told me the eviscerating teeth will engage for approximately 20-30 seconds before the waste discharges.
Could you tell me what this problem may be, and how to correct it?
Thank you kindly!