1#feinet2001 ! @6 ~/ `% j7 g* W, ^0 w- `6 v w/ Y% ^
option 1: Two seperated furnances and seperated control7 {8 x6 n/ f, N. P8 v
(for big house > 3000 ft) ) V- u! {' Z, S' a) h/ `, Foption 2: One furnance with Zone Control device 1 W R8 t& A& U2 }0 f. e. u: V/ P (three zones or fours zone will be good) - total efficiency will be higher + D8 n" b, {% b* n% @4 m# B$ H5 ~) K9 x3 l2 v
Total cost is not big difference.