Does filter pump have to run use heat for pool?

Yes, the filter pump must be running in order to use the heat pump for a pool. This is because the filter pump circulates the pool water through the heat pump, which then heats the water and returns it to the pool. If the filter pump is not running, the heat pump will not be able to properly circulate the water and heat the pool.

Additionally, running the filter pump helps to keep the pool water clean and free of debris, which can also help to improve the efficiency of the heat pump.