Grunfos Mq cold water booster pump

[balliancian]

Hi, Its my first time posting here, lots of you guys know your pumps!!
I have a grunfos Mq booster pump boosting my domestic cold water into the house. Recently it has started turning its self on and off intermitantly,on for 15 seconds then off for 1 minute.
I have checked for obvious above ground leeks. Could any of you guys be able to tell me what coul dbe the problem.
Thanks in advance!

 

[waterwelldude]

It sounds like you may have a leaking check valve.If you have looked for leaks after the pump, and could not find any, I would look to a bad check valve.

 

[Mr_David]

Check for any leaks in the house. It could even be a leaking flapper on a toilet. The pump is cycling because the system is loosing pressure some where.