Dampers

Fred Harwood

One small problem with home heating is the amount of inside air heading up the chimney through the draft damper both while the burner operates and when it's not. All that warm air must come from outside, either through special breeches, or, as in most cases, through the crack at the bottom of the garage door and general infiltration. At times, that outside air is well below zero.

Automated draft dampers help, but have problems of their own. Has anyone successfully experimented with eliminating the draft damper by, in essence, orificing the flue pipe to give the appropriate over-fire draft? That way, without an open draft damper most of the heated air stays in the building rather than fleeing up the flue. With a burner such as the Beckett AFG, losses will be very small. All thoughts welcome.

Ted_4

Damperless

Yes, I did just that on the W/M Gold I installed in my home 10 years ago. It has been running over that time with no problems. The AFG produces a very high static pressure, so chimney draft changes have little/no effect on performance. I installed the Beckett automatic air inlet damper because the overfire draft rises to chimney draft level when the burner is off. With this arrangement I see a very rapid drop off of flue temperature when the burner cycles off. I'm very happy with this arrangement, and don't understand why most boiler manufactures still recommend installing barometric dampers. However, I noticed that the installation manual for H B Smith 8 series says to install a damper only if the chimney draft is above .04 w.c.!!