12
PRACTICAL
TIPS
INSTALLING DUCTS TO / FROM INSIDE
• The fresh air inlet from
the HRV needs to ensure
proper air mixing and
temperature in the air
handler. Units should be
interlocked with one
another so that the air
handler runs, when there
is a call for ventilation.
• Units may be operating at
different static pressures.
Compatibility of the two
(2) systems must be veri-
fied by checking that bal-
ance of the HRV/ERV
found in this manual.
Notes: See air handler
manufacturer for
appropriate
specifications.
Direct Connection to Furnace/ Air handler return duct
• Should you wish to hard duct the supply air directly into the cold air return of the
HVAC systems, remember to check the airflow balance of the HRV with the HVAC
systems fan both “on”and “off” to determine that it does not imbalance the HRV
more than 10%. Make sure you respect the minimum distance from the supply air
in of the HRV/ERV and the HVAC systems (Refer to your local and National
Building & Heating Codes for any variations in these notes).
• It may be necessary to install a separate fresh air supply ductwork system if the
heating is other than forced air.
When installing an HRV/ERV, the designer and installer should be aware of local
codes that may require smoke detectors and/or firestats in the HVAC or HRV/ERV
ductwork.
Because an HRV/ERV is designed to bring fresh air into the building, structures
may require supply voltage interrupt when smoke or flame sensors are triggered,
or when a central fire alarm system is activated.
* See installation examples found in this manual.
To maximize airflow in the ductwork system, all ducts should be kept short and have as few bends or elbows as pos-
sible. Forty-five degree are preferred to 90˚ elbows. Use “Y” tees instead of 90˚ elbows whenever possible.
All duct joints must be fastened with screws or duct sealant and wrapped with a quality duct tape to prevent leakage.
Aluminum foil duct tape is recommended.
SUPPLY AIR DUCTING
In buildings without a forced air HVAC systems, fresh air should be supplied to all habitable areas. It should be sup-
plied from high wall or ceiling locations. Grilles that diffuse the air comfortably such as Fantech grille {MGE (metal)
or PGE (plastic)}s are recommended.To avoid possible noise transfer through the ductwork system, a piece of flexi-
ble ducting should be connected between the HRV and the supply ductwork system.
If the floor is the only option available, then special care should be taken in locating grilles. Areas such as under
baseboard heaters will help to temper the air. Also optional inline duct heaters are available for mounting in the sup-
ply duct work to add heat if required.In buildings with a forced air HVAC systems, you may want to connect the HRV
to the HVAC ductwork (see information below).
