1#feinet2001 & H# r( U7 k2 B" Y1 K# b9 y0 ~! Z" M" G. J! D& }
option 1: Two seperated furnances and seperated control! R3 B, R+ a$ |9 @- p
(for big house > 3000 ft) 9 I* G) N0 {# G8 a( i g ?) Soption 2: One furnance with Zone Control device 7 \ w* j1 [$ a2 i! Q
(three zones or fours zone will be good) - total efficiency will be higher5 J+ a% h8 T' l# i& i+ A c
& c5 g" ]7 g e9 v8 ]Total cost is not big difference.