本帖最后由 ram 于 2011-10-14 07:48 编辑 % u1 e6 ]4 j$ A. w4 Q* P3 s/ G) L+ k
" ?; C9 y. j% }6 |9 T( r 7#laoxi $ X7 E6 G! U* G" F $ Y) A, c' g4 w1 I- v0 y: S+ R# p9 ]# \The problem is that there is more energy exhuasted by flue if heating system is less efficient.