Pennsylvania Water running constantly

I have an open loop system that the water is running continuously when it is not calling for heat/cooling. changed the solenoid out and diaphram in check valve and it is still running? Nothing has been changed on the system. Any help is greatly appreciated.

 

I would make sure the valve is moving. How and where is the valve tied into the heat pump?

Mark

 

Thanks for the reply. Found the valve had a small crack in it. Thanks again