1#feinet2001 $ f% A. b5 A- W2 l0 d8 j3 u- |- q3 ^- p! ?$ X% ]5 j& {3 T- _# C
option 1: Two seperated furnances and seperated control $ R$ v0 m2 \' m (for big house > 3000 ft) $ @1 s1 E7 D Foption 2: One furnance with Zone Control device / S( B; Z: `6 @4 ]' o (three zones or fours zone will be good) - total efficiency will be higher. N7 Q" G( P/ }: O- J, q% c
9 E; J/ T3 r8 C0 C/ ~Total cost is not big difference.