This will stop the air from getting a free ride along the chase and heating your attic.
Clear attic furnace flue.
How to check for creosote.
Because the pipe gets hot building codes usually require 1 inch of clearance from metal flues 2 inches from masonry chimneys to any combustible material including insulation.
Not much furnace experience around here that s just a heating coil on the end of the a c blower used for 7 8 weeks a year g.
While you are at it look around for all other duct chases in your attic.
Furnace flues require special sealing techniques the opening around a furnace or water heater flue or chimney can be a major source of warm air moving in the attic.
Apply a thick bead of high temperature caulk the flue on one.
The vent should always be clear.
Then use fire rated caulk to seal the gap btw the sheet metal and flue and then the sheet metal to the attic floor.
I try to always design in some slop in spacing around mechanical equipment.
Nail them both on the attic floor so they butt up against the flue.
You can reduce creosote buildup in your fireplace flue by providing adequate combustion air which will encourage a hot clean burning fire.
To check for creosote yourself first make sure there s no downdraft from the chimney.
Because the pipe gets hot building codes require 1 in.
See direct vents side wall vents for a complete table of recommended clearance distances from a direct vent gas appliance terminal to other building components or features.
Wipe it clear with a rag or soft cloth and then replace the cap.
Remove the insulation between the joists where the flue is located to clear an area about 18 inches away from the flue on each side.
American gas association has certified the design of condensing furnaces for a minimum of 0 clearance from combustible materials with a single wall plastic vent pipe.
The opening around a furnace or water heater flue is a major source of warm air into the attic photo 5.
Cut away any branches or remove any object that might be obstructing the pipe and creating debris.
The vertical flue at the ceiling level is surrounded by and attached to a horizontal piece of open 1 2 x 1 2 metal mesh screen about 10 square.
Municipalities may require a minimum of 30 clear inches in front of the furnace which can be accomplished in a small room if the door to the room opens in front of the furnace.
Of clearance from class b flues 2 in.
2015 irc m1305 recommends that the furnace have a level working space of at least 30 inches by 30 inches in the front of the appliance.
