20
21
Summeraire HRV Air Flow Balancing
A. Preliminary Procedures:
1. Seal all the unit’s ductwork with foil tape.
2. Close all windows and doors and fireplace damper, turn off all exhaust
devices (range hoods, clothes dryer, bath fan, etc.), make sure all filters are clean.
3. Set build-in balancing dampers fully open. Tap 1/8” hole in ductwork for
pitot tube insertion.
B. Balancing Procedures:
1.Set HRV to high speed. Make sure that the furnace blower is ON if the
installation is in any way connected to the ductwork of the furnace. If not,
leave the furnace blower OFF. Adjust air flow in branch lines if using source
point exhaust and/or supply.
2. If outside temperature is below -3°C (26°F), make sure defrost light is not
on while balancing.
3. Place magnahelic gauge on a level surface and adjust it to zero. Insert pitot
tube into exhaust air ductwork with tip aligned with ductwork, pointing away
from HRV, into air flow. Record the reading on gauge.
4. Move kit to other air stream HRV, insert pilot tube into fresh air ductwork
with tip aligned with ductwork, pointing towards HRV , into air flow.
Record reading on gauge. Adjust fresh air balancing damper until reading is
approximately the same as in exhaust air ductwork. If the reading in the fresh
air ductwork is less than in the exhaust air, go back and adjust the exhaust
balancing damper to equal the fresh air flow.
5. Secure dampers in place with fastening screw. Duct tape over pitot tube
holes.Convert FPM reading on gauge to CFM with conversion chart and
record on balancing sticker and affix to HRV near label.
6. Note: Unit is considered balanced if readings are /- 10%.
