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VI. EP62R A/C Control and Output Alarm Connections
Depending on the customer input signal the air conditioner works in five different modes:
■
Cooling air conditioner mode
■
Cooling economizer mode
■
Heating mode
■
Purge mode
■
Smoke alarm mode
The customer could send one of four 24V A/C signals:
1. Cooling air conditioner mode
The compressor, the condenser and the evaporator blower are running, keeping temperature inside of
the enclosure between 75°F and 115°F, depending on internal load and ambient temperature. The
economizer damper is in the closed position.
2. Cooling economizer mode
At ambient temperatures below 55°F. the unit works in the cooling economizer mode. The compressor
and the condenser blower do not run. The evaporator blower runs constantly, drawing air from the
outside through the air filter and the enclosure, then discharging air to the outside through the
economizer damper. The cooling economizer mode keeps temperatures inside the enclosure about
80°F.
3. Heating mode
When in heating mode the unit keeps temperatures inside the enclosure within the range of 55°F and
71°F by activating the electrical heater.
4. Purge mode
At any ambient temperature the unit works the same way as it does in the cooling economizer mode -
the economizer damper is open and the evaporator blower is running.
5. Smoke alarm mode
In this mode the economizer damper is closed, and the evaporator blower does not run.
Input signal
Wire color
Common
Red
Cooling request
Black
Heating request
White
Purge alarm
Blue
Smoke alarm
Brown
