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. Stale Air Return System
The stale air return system is used to extract humid, stale air from the areas
of the dwelling where the worst air quality conditions might exist. These may
include areas such as laundry rooms, bathrooms and kitchens. Note that C.S.A.
Standard F326 requires that air be exhausted from each room with a forced air
furnace.
Wall stud spaces can be used as ducting for high wall returns provided that they
are lined with galvanized metal.
Note: Check local code compliance before implementing.
Adjustable “Tech Grills” are recommended for use in the return air system. They
can be wall or ceiling mounted thereby permitting balancing of the air being
exhausted. Stale air return grills should be located at opposite ends in the room
to the fresh air grills to ensure good air exchange.
Please note that the exhaust air stream from a kitchen area must never be
connected to the kitchen range hood. Instead an exhaust grill should be mounted
high on the wall as required by local codes so as not to extract cooking by
products.
9. Air Flow Balancing
READ THE APPLICATION WARNING AT THE FRONT OF THIS MANUAL.
A magnehelic gauge and pilot tube flow measuring system is used for
easy and accurate air flow measurement
Upon completion of the installation it is necessary that the Ventilation System
be balanced. This is necessary to ensure that the volume of air being exhausted
from the dwelling is equal to the volume of air being supplied. Balancing will
also ensure that the HRV is operating at it’s maximum efficiency.
Detailed check list to be carried out prior to balancing.
a) Install air flow station in each of the warm air streams.
b) Ensure that all ductwork is secured and sealed.
c) Drain connections are in place and drain trap filled with water.
d) Dwelling vapour barrier is complete and intact.
e) Fireplace dampers, windows and doors are closed.
