Quadra-Fire 7051-158B User Manual

Page  40

7051-158B

December 6, 2011

R 

Negative pressure results from the imbalance of air avail-
able for the fi replace to operate properly. It can be strongest 
in lower levels of the house.

Causes include:

•  Exhaust fans (kitchen, bath, etc.)

•  Range hoods

•  Combustion air requirements for furnaces, water heaters 

and other combustion appliances

•  Clothes dryers

•  Location of return-air vents to furnace or air conditioning

•  Imbalances of the HVAC air handling system

•  Upper level air leaks such as: 

 

-  Recessed lighting

 

-  Attic hatch

 

-  Duct leaks

To minimize the effects of negative air pressure:

•  Install the outside air kit with the intake facing prevailing 

winds during the heating season

• 

Ensure adequate outdoor air for all combustion appliances 
and exhaust equipment

•  Ensure furnace and air conditioning return vents are not 

located in the immediate vicinity of the fi replace

•  Avoid installing the appliance near doors, walkways or 

small isolated spaces

•  Recessed lighting should be a “sealed can” design

•  Attic hatches weather stripped or sealed

•  Attic mounted duct work and air handler joints and seams 

taped or sealed

Draft is the pressure difference needed to vent fi replaces 
successfully. When a fi replace is drafting successfully, all 
combustion byproducts are exiting the home through the 
chimney.

Install through the warm airspace enclosed by the building 
envelope. This helps to produce more draft, especially dur-
ing lighting and die-down of the fi re.

Considerations for successful draft include:

•  Preventing negative pressure
•  Location of fi replace and chimney