High efficiency furnaces take advantage of the heat in the combustion gases that are wasted in natural ventilation systems.
Roof pipe from furnace.
It draws air from within the house for combustion.
The vents consist of circular or oblong pipe that attaches to a flange on the furnace and extends.
Gases produced during combustion are very hot and as such easily rise through the flue.
The master flow 4 in.
Vents can also be terminated above the roof.
Rubber electrical mast split pipe boot roof flashing in black model 81746 37 27 37 27.
If your furnace has an afue rating of 90 or lower it probably exhausts the gases though the flue pipe on your roof.
Goose neck vent the master flow 4 in.
Set your store to see local availability add to cart.
Perma boot vent pipe repair for 4 in.
Goose neck vent in black can be used to cover exhaust pipes extending through your roof or for attic ventilation.
Vent pipe in black model pbr 312 4bk 19 97 19 97.
This vent is designed to be used on 4 in.
Another problem is that flue pipes that go through the roof tend to be less efficient.
Gibraltar building products 11 in.
The air is then vented outside through a b vent pipe which is set vertically to expel combustion air through the roof.
It provides a vent pipe for exhaust gases but uses unconditioned not cooled or heated air from the space around the furnace for combustion air.
Type b vents are a standard design that most modern gas furnaces use.
The single pipe non direct vent system is used where there is no real need for a separate combustion air intake vent.