Lennox FCM 85 Installation, Operating And Maintenance page 45

ENERGY RECOVERY INSTALLATION
STEP 8: Roof curb economiser Adjustment
With Heat Recovery module option the extract air goes through the wheel, that's why the
economiser of the roofcurb has to be permanently fully closed.
If roofcurb economiser is not fully closed, close it manually
And don't connect the actuator to the rooftop.
Actuator Roofcurb
not connected
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