本帖最后由 ram 于 2011-10-14 07:48 编辑 0 h( N# P& ~3 S _; R% ]
6 K. p/ i- j1 [8 q2 i8 w8 e8 r 7#laoxi 3 [ K, D8 S6 a8 [( s9 }& X/ F3 A+ @ # G& C" F0 v, s/ T: X3 R3 EThe problem is that there is more energy exhuasted by flue if heating system is less efficient.