多谢大家。还有一个问题,你们的exhaust vent是走suffit的呢,还是走房顶的?我家的是走suffit。根据下面的问答,好象要装这个 ventilator 必须要把 exhaust vent 改道。你们有改道吗?不改道是不是装了也没什么用?谢谢谢谢!
Question: I have installed your ventilator on my roof, but I am  			still having some ice damming over my kitchen and washroom area.  			Should I install another vent?
 			Answer: No, we recommend that you verify your exhaust vents for  			your washroom dryer and kitchen stove. They are probably venting  			into the attic space or into the soffits which is a common practice  			in the building industry. We recommend that you have them rerouted  			out threw the roof using our model CT-4 which was designed for this  			purpose. The goal of attic ventilation is to remove moisture from  			the attic, not introduce it into the attic.