Field Controls Heat Recovery Ventilator FC95HRV. - Manual (Page 9)

Port Configuration and Airflow Model FC95HRV
In order to make the HRV as space efficient as possible, the
INDOOR supply and return ports are converted from round to oval
shape. Overall size of the port remains the same. Simply bend a
standard duct fitting to the correct shape, and attach to the oval
port using the same method as for a round port.
FC95HRV Air Flow
Stale air enters the FRONT-RIGHT side port. The air passes down
the front half of the core, then up the back half of the core and out
the RIGHT-REAR port.
Fresh outdoor air enters the LEFT-REAR port and passes down
the back half of the core. Then the fresh outdoor air passes up the
front half of the core and out the LEFT-FRONT port. This
configuration allows the air to actually travel through the core
twice, which makes the FC95HRV nearly as efficient as a double
core unit.
Round port bent to oval
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