Nu-Air Ventilation Systems Inc. - HRV Operating &Installation Manual
Revised April 27, 2012
Page 10 of 17
6.10
Balancing the System
Balanced airflow between the supply and exhaust air streams is essential to the performance of
an HRV.
The pulleys used on the supply and exhaust fans are a split type pulley that allows some field
adjustment of the fan rpm and corresponding air flow. Adjust the pulley in ½ turn increments.
Close to increase rpm, open to decrease rpm.
Once the HRV system is installed, do the following:
•
Close all windows and doors.
•
Turn off any exhaust only systems.
To balance the HRV, set the machine on high speed.
•
Make a small hole in the supply duct at least 10 feet downstream of the fan. Insert a Pitot
tube in the cross sectional center of the duct.
•
Measure the pressure with a digital manometer or magnehelic gauge.
•
Record the value and repeat the procedure for the exhaust air stream.
•
Install a balancing damper in the air stream with the greater flow and damper back until
the pressure equals that of the opposite air stream.
7
ELECTRICAL POWER & CONTROLS
For electrical hook-up, the HRV should be connected to a power source of voltage and phase
indicated on the name plate and according to applicable local electrical codes.
