LOW TEMPERATURE COMPRESSOR LOCKOUT
Economizer Control
OUTDOOR DRY BULB CHANGEOVER— The standard controller is shipped from the factory configured for outdoor dry bulb changeover control. The outdoor air and supply air temperature sensors are included as standard.
For this control mode, the outdoor temperature is compared to a selectable set point on the sensor. See Fig. 39. If the
In this mode of operation, the
EXHAUST FAN
SETPOINT
LED LIGHTS WHEN
EXHAUST CONTACT
IS MADE
MINIMUM DAMPER
POSITION SETTING
MAXIMUM DAMPER DEMAND
CONTROL VENTILATION
SETPOINT
LED LIGHTS WHEN
DEMAND CONTROL
VENTILATION INPUT
IS ABOVE SETPOINT
DEMAND CONTROL
VENTILATION SETPOINT
LED LIGHTS WHEN
OUTDOOR AIR IS
SUITABLE FOR FREE
COOLING
ENTHALPY
CHANGEOVER SETPOINT
A09708
Fig. 38 - Economizer Controller Potentiometer and LED
Locations
(8.9°C)
(11.7°C)
(12.8°C)
(14.4°C)
(17.2°C)
(20°C)
(22.8°C)
(25.6°C)
A10134
Fig. 39 - Outdoor Air Temperature Changeover Set Points
ECONOMIZER |
RETURN AIR
SENSOR
RETURN DUCT
A09710
Fig. 40 - Enthalpy Sensor Mounting Location
40