I am getting bids for a split system for a new house. I spoke to an American Standard contractor (highly regarded) today and asked them for recommendation. I don't have the bid yet but we discussed issues like sizing and SEER and AFUE ratings. House if 3139 sq ft and architect plans provides for a spilt system (4 ton and 2.5 ton). I am located in central California (hot, relatively dry summers and mild winters).

AC Recommendation

His preliminary recommendation was to go with a 12 or 14 SEER AC (14 SEER with a 2 speed fan) and use an oversized coil to increase efficiency. I asked if this would create a problem with warranty and he assured me it would not and that using an over sized coil was a common method to increase efficiency. He said this would give me reasonable efficiency without the extra cost of an 18 SEER unit.

Heating Recommendation

He recommended using an 80 AFUE system with a variable speed fan (or two stage valve? Sorry, can't remember). He said for your area the cost of a 90+ AFUE system would not be cost effective.


Contractor said he would do a calculation but said 6.5 tons for our area for the house size sounded about right.

Any comments from the professional members? Any other questions I should ask.

Thanks very much.