furnace damper

can anyone tell me what is the function of this damper

DSCF0016 (Small).JPG

It’s called a “barometric”–it adjusts the air to the flue for draft.
It is the same function as a draft diverter on a gas furnace.

Thanks

Earl
By any chance is this damper on the furnace serviced by the oiltank you posted about yesterday?
Larry

Yes it is from the oil burning furnace.

Figure 1 Oil-fired forced-air furnace

http://oee.nrcan.gc.ca/Publications/infosource/Pub/home/images/figure1.gif

thanks

Tyron. nice diagram for a forced warm air system. have you got one for forced hot water? i like to carry such diagrams with me to show client so they can better understand.

Is this what you need?

http://oee.nrcan.gc.ca/publications/infosource/pub/home/images/fig6.gif

Tyrone, that works thanx again. looks like hanging on to those text books paid off, huh?