Heating, Air Conditioning, Fridge, HVAC/Air Conditoner


I have a summer home that is located in a warm climate.  We are replacing the air conditioning unit (a single stage Carrier) because of its noise (the neighbors have complained) and its struggle to maintain a temperature in  the 70s without running all the time. I have been getting bids and they vary quite a bit.  I have been told by one contractor that in order to have a 2 stage AC Unit work I would need to change out the furnace blower and circuit board in order for the AC unit to function  in 2 stage mode. Others have said that a 2 stage AC unit will work fine with a single stage blower on the furnace.  Can you please address this issue?  Also, am I better putting in a single stage with a seer of 14 or 15 than a 2 stage with a 17 seer rating?

Most air conditioner condensing units are sized for twenty degree differential between inside and outside temperature and they run all day.
It depends on your furnace what you can and cant do as far as two stage blower but you can use the existing furnace if it's compatible CFM wise with your AC unit.
Personally I would rather have a single stage unit all the way. seer is just how much electricity it takes to run your outside unit, it has nothing to do with performance or cost of running the inside unit.

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

Hands on since 1950

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