Multi-Unit Residential HRV/ERV
11
Locating the Air Exchanger
The device must be located in a place where the temperature is always above freezing.
Choose a location for the device where the ducts will be short with minimal use of
elbows. This ensures that the system functions optimally.
Ducting Materials
1. Where ducting passes through concealed spaces (walls, ceiling-floor assemblies), the
ducting should be metal to offer less resistance to airflow and permit duct cleaning.
2. Where the ducting remains permanently accessible, 5 to 10 feet of insulated flexible
duct should be used between the HRV/ERV and all interior supply and exhaust registers
to reduce fan noise passing the ducting to interior spaces.
Connecting the Ducts
For the air exchanger to run optimally, place the ducts so they are as straight as possible.
Ducts should be kept short and have as few bends or elbows as possible to maximize airflow.
Forty-five degree elbows are preferred to 90-degree elbows. Use “Y” tees rather than straight
tees whenever possible.
All ducts going through unheated areas must be insulated. The ducts between the exterior
vent hoods and the HRV/ERV must be insulated and covered with a vapor barrier. See the
next section “Vent Hood Locations”.
Flexible duct is recommended to provide vibration isolation between the unit and duct
system. Start by determining the required duct length to reach each respective collar, and
cut as required. If rigid duct is used, avoid attaching with screws to the duct collars, as they
may interfere with the damper operations at each duct collar.
H80 and E80 models are equipped with twist-in collars to simplify the process of connecting
flexible duct to your ventilator. Remove each duct collar by twisting them out of the locking
tabs. Connect the ducts to the removed collars using duct tape and flexible duct straps.
Reinstall collars, with duct attached, to their respective labeled ports on the HRV/ERV by
lining up locking tabs and twisting on in a clockwise direction.
For H130 and E130 models, connect the ductwork to the collars on the unit using duct tape
and flexible duct straps.
*Note: for illustration purposes only. Unit is not to be installed as shown.