I have an air-source heat pump with all ductwork in the basement. I live in central Pennsylvania. In the summer, if outside temperatures are 85 degrees-100 degrees I want to cool the house to 75 degrees. I have a full underground basement (about 1800 sf) that stays around 65-80 degrees. If my outside HP/AC coils were in the basement (and I had a cold air inlet in the basement) my HP/AC would do much less work, use less electricity and maybe even need a smaller unit than an outside one. Basically going from 65-80 basement degrees to 75 degrees instead of 85-100 outside degrees to 75 degrees.
Same deal for heating in the winter. Outside temps 0-70 degrees outside and 40-60 degrees in basement. Basically going from 40-60 basement degrees to 70 degrees instead of 0-70 outside degrees to 70 degrees. Much less work for the HP.
Where is my logic wrong? What are the problems with doing this (if a professional would actually install it I'm eventually going to need to replace my 18 year-out heat pump and with the rising price of all energy, I thought placing it in the basement could save electricity/heating/cooling costs and initial installation of a smaller unit.
Thanks in advance!