Automatic Defrost; Wiring - Honeywell VNT5150H1000 Installation Manual

Automated Defrost
The ERV and HRV units are equipped with an automatic defrost feature to eliminate any ice build up on
the core.
• Automatic defrost is initiated once every hour when the fresh air supply temperature drops to 23°F
(-5°C) or colder.
• The defrost cycle operates by turning off the supply fan while continuing to operate the exhaust fan.
• The exhaust fan speed is adjusted proportionally based on the outdoor temperature, initially operating
at low speed.
• As the outdoor temperature continues to drop, the exhaust fan speed will increase, and will operate at
maximum speed when the outdoor temperature is -4°F (-20°C) or less.
• Defrost cycle runs for 4 minutes with the supply fan off, followed by 40 minutes of continuous normal
operation.
• Defrost cycles will continue to repeat as long as the temperature is 23°F (-5°C) or less.

Wiring

CAUTION: Voltage hazard.
Can cause equipment damage.
Disconnect power from the unit before beginning installation.
Terminal Description
The wiring terminal block is located behind the control module door on the side of the unit.
To access the terminal block, open the control panel door by swinging it open and to the right as shown
above.
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ERV/HRV Ventilation Systems 69-2480EF—01
M28986