Hello - I am renovating a house and facilities for myself and family. I am not a heating engineer. There is a 25kW air to water vertical standing heat pump ( no brandname). It heats a 14k gallon swimming pool.  The fan on the top has broken. It appeared to be blowing air out vertically when it was operating. I don't know if the replacement fan should be a suck or blow fan?  I believe that air will move up inside the heat pump travel over the motor, then to the fan and then out of the top of the unit, so I believe the fan will be a blow orientation.  Before I make an expensive mistake, I wondered if anyone could advise me??   Hopefully if I get it wring there will be no damage. Many thanks Brian 

The fan on those blows the air UP.

Thanks very much - great help.