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B
ALANCING THE
A
IRFLOWS
Balancing the airflows is critical to ensure that the amount of air coming into the building equals the amount of
air exhausted to the outside of the building. If these two airflows are not properly balanced, the following
issues may occur:
•
A positive or negative pressure in the house
•
HRV will not operate at its maximum efficiency
•
HRV will not defrost properly.
Airflow Measuring Gauge:
•
A digital manometer is a suitable instrument for the
balancing of airflows.
Airflow Balancing Kit:
•
Kit includes a digital manometer, pitot tubes, hose,
adapters, and tool bag.
Gauge Attachments:
When sampling an airflow, various attachments are available for use on a
digital manometer. Consult with your Lifebreath distributor for available
options such as a pitot tube, flow measuring station, and an airflow
measuring probe. The illustration below shows a digital manometer with a
pitot tube attachment. This combination will measure the system air
velocity pressure accurately, regardless of the duct size or shape (either
round or rectangular).
Balancing Preparation:
Prior to performing the air balancing procedure, perform the following
steps:
1.
Seal the ductwork.
2.
Confirm the installation and proper operation of all the components of the HRV.
3.
Fully open the balancing dampers.
4.
Turn of all household exhaust devices (range hood, clothes dryer, bathroom fans).
5.
Set the HRV at high speed.
6.
Prior to balancing the unit, first adjust airflows in the branch lines to specific areas of the house.
7.
If the outdoor temperature is below 0°C (32°F), ensure the unit is not running in defrost.
8.
If the system is a Simplified or Partially Dedicated installation, operate the furnace/air handler at high
speed.
Attention
•
Continuous, excessive, positive pressure may drive moist indoor air into the external walls of the building.
Once inside the external walls, moist air may condense (in cold weather) and degrade structural components
or cause locks to freeze.
•
Continuous, excessive, negative pressure may have several undesirable effects. In some geographic
locations, soil gases such as methane and radon gas may be drawn into the home through basement or
ground contact areas and may also cause the backdrafiting of vented combustion equipment.
Airflow Balancing Kit (99-BAL-KIT)
