Thank you; that’s good information.

What should the homeowner have done instead? To make sure that all fuel burning appliances are shut off, including any pilot lights, during the drying process?

They should have left a widow open so the home did not become starved for air .


Just about anyone who works on houses now should have a course (should be mandatory) on house pressures, combustion spillage and backdrafting. The WETT system now has 2 one day courses on these topics to expand upon the basic introduction of the “House-as-a-System” concept introduced in the basic introductory “core” program leading to inspector or technician certificates (after appropriate field time, etc).

In 1989, I worked in Halifax as part of a cross country study on general indoor air quality. Another section in the study was to test oil/gas/propane furnaces and boilers for combustion spillage upon firing up. It was found that almost 40% of these brown appliances spilled exhaust gases!! This was appalling as this 40% obviously had weak/poor chimney draft and any system could be easily put into a flue reversal by use of a strong bathroom/kitchen fan or something as simple as opening a window on the second floor of a house.

I would think that this fan woud cause some concern?:shock: http://www.wholehousefan.com/theghost.html

What I have discovered since getting an IR camera that those cheap plastic 4 little flapers on the dryer vent are absolutely useless.
Bathroom fan kitchen fan and in comes a lot of air .
Shut of the fan and the stack effect tends to keep drawing in cold air.
The Metal spring loaded ( cost about $12;00 ) work much better.

</IMG> Only seen one whole house fan and that was 30 years ago.
I expect they only used in hot weather.
I wonder how tight they close or could they loose a lot of warm air in the winter?
Of course it would be very hard to get into the attic with one of these in the way.


Seen a few of them here, yes they are used in the warmer weather but so is the HWH, as are pilots on furnaces etc. Usually them seal with a lid to stop the heat lose in the winter, but they are very strong and move a lot of air fast. As for getting into the attic they are usually in very large homes and so lots of room to have a hatch.