The airflow in my house (two floors, no attic) is currently done with two exhaust fans on the roof. The house has two airduct systems for each fan. One is servicing garage, indoor swimming pool and basement. The other sucks air out of bedrooms etc..
Recently I've been looking into AC with heat exchanger. This is Scandinavia so I'd like to collect heat before it is exhausted out of the house.
Because the house has two air duct systems I'm looking into two separate AC systems. I don't mind buying them from overseas as local models are expensive.
My plan is the following:
1) remove the roof fans and cap the holes 2) Connect the ac machines into extinsting airduct in one of the rooms or basement and provide exhaust pipe to outside.So I would be using existing air ducts.
What problems I may be facing? Can you recommend any models? The climate is mild in summer and regular airflow is sufficient for summer.