The choice of the pump

The actual head of the wilden pump is the vertical distance of the surface to the water + piping losses. You need the actual head is the water of 3 m + storey 7 m + below 47 m loss is about more than 7 meters, that is, you will be able to pump more than 17.5 meters lift normal use, the traffic you need to choose.

If you want to use for water source heat pump, you should also consider whether the water source heat pump requires pressure, if necessary pressure must add the corresponding pump head. Given that you are for the water source heat pump, the flow requirements is not too high, but requires high quality of the pump. Is the continuous work and power consumption requirements and I advocate that you use 100QJ pump. 370W will be able to meet your needs. Lift 35 meters. Of course, can choose to 550W of the head 45 meters, but wilden  pump less than 80% of the actual head. Power consumption will be floating.