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fantech
INSTALLATION EXAMPLES
(CONT'D)
DIRECT CONNECTION of both the ERV SUPPLY AIR STREAM and EXHAUST AIR STREAM
to the FURNACE COLD AIR RETURN
SIMPLIFIED INSTALLATION (GOOD)
(RETURN/RETURN METHOD) - OPTION 1
1. Furnace blower must operate when ventilation from ERV is required. The
furnace should be set to run continuously or interlocked with ERV.
See
furnace electrical connection on page 18.
2. A minimum separation of 1m (39’’) is recommended between the two
direct connections.
3. In order to prevent exhausting any fresh air, the ERV’s exhaust air connection
should be upstream of the ERV’s supply air connection when ducting to the
furnace’s cold air return.
4. Due to the difference in pressure between the ERV and the equipment it is
being connected to the ERV’s airflow must be balanced on site, using the
procedure found in the section “AIRFLOW BALANCING”
* In the case of a multi-zone system, please contact Fantech customer
service prior to installing any installation type requiring the use of the
furnace interlock"
Fantech energy recovery ventilators (ERV) that use a supply fan shutdown for frost
prevention do not include an outdoor air motorized damper. If you are using a simplified
installation, i.e. connecting the ERV supply air duct to a furnace's return air duct, the ERV
must operate continuously. When the ERV is turned off, no warm exhaust air will flow
through the ERV but the furnace's fan will continue to draw in outdoor air directly into the
furnace. If it's cold outside, cold air will be introduced, without re-heating, directly into
the furnace.
If the ERV is installed such that the homeowner may turn off the ERV during the winter, we
recommend installing a motorized damper between the ERV's supply air and the furnace's
return air duct that closes when the ERV is not operating. See wiring diagram (figure 1).
Damper
Motor
24 VAC Transformer
COM
NO
ERV Furnace interlock
See page 18.
24V
120V
Figure 1
*Transformer and Damper motor not included
Suggested installation for:
• When bathroom and kitchen
already have local exhaust
system
• May be suitable for
retrofitting
Benefits:
Least expensive
installation type
Stale air from inside
Outside
Fresh air to
living areas
1 m (3' 3")
min.
recom-
mended
Cold air
return
Stale air to
outside
Fresh air from
outside
* Unit airflow should be balanced while HRV is on
“Normal” speed and furnace blower is running.
Motorized
Damper
1 m (3' 3")
min.
recom-
mended
ERV/ furnace for Simplified Installation – Option 1
