23
Balancing Preparation
Prior to performing the air balancing procedure, perform the following steps:
Seal the ductwork.
Confirm the installation and proper operation of all the components of the ERV.
Fully open the balancing dampers.
Turn off all household exhaust devices (range hood, clothes dryer, bathroom fans).
Set the ERV at high speed.
Prior to balancing the unit, first adjust airflows in the branch lines to specific areas of the house.
If the outdoor temperature is below 0
o
C (32
o
F), ensure the unit is not running in defrost.
If the system is a simplified or partially dedicated installation, operate the furnace/air handler at
high speed.
Balancing the Airflow With a Pitot Tube
Step 2:
Insert the pitot tube with the tip facing towards the air
stream in the stale air from Building air stream. Move the pitot
tube around in the duct (facing toward the airflow) and take an
average reading. Record the reading.
Step 3:
Repeat step 2
to measure the fresh air to building duct.
Pitot tube tip facing
towards the air stream.
Balancing
Damper
Drill 3/16 in holes in
Stale & Fresh air
ducts.
Fresh Air to Building
Balancing Damper
Step 1:
Drill a 3/16 in hole in the duct, ideally 3
ft downstream and 1 ft upstream of any elbows
or bends in the fresh air and stale air streams.
Stale Air from Building
Pitot tube tip facing
towards the air stream
Balancing Damper
Step 4(a):
Review the readings and damper down the duct with
the highest duct velocity pressure. Repeat step 2 and step 3 until
both ducts show identical readings.
Step 4(b):
Upon completion of balancing, seal the holes (foil tape
recommended).
Seal holes.
Balancing
Damper
