Friedrich PTAC operation manual F. Fan Cycle Switch, G. Fresh Air Vent Control

920-087-02 (9-03)

E. Heating Control (heat pumps and emergency heat operation)

NOTE: Heat pump models only. Heat pump equipped models use backup electric resistance heating coils. At extremely low, outdoor ambient temperatures, the heat pump is automatically disabled and the unit operates solely on electric resistance heat.

This control is located behind the decorative front cover and is found on the right side panel of the chassis. Its function is to allow you to set the temperature range in which the heat pump operates. This control switches the unit heat operation between heat pump and electric resistance heat based on the outdoor ambient temperature. These change-over temperatures are based on the settings of the control. The factory setting is at the one o'clock position. If you wish to change the factory set point, insert a flat-bladed screwdriver into the slot and turn counterclockwise to increase the changeover set point, or clockwise to decrease it.

NOTE: The factory set point is recommended for optimum performance.

NOTE: Emergency heat operation only. In the event of a compressor malfunction in the heat pump mode, turn the screw to the extreme counterclockwise emergency heat position. The heater will then cycle using electric resistance heat only. Note that in the emergency heat position, the compressor is locked out, disabling both heat pump and cooling operations. CALL A SERVICE PERSON. DO NOT FORGET TO RETURN THE CONTROL TO ITS ORIGINAL POSITION AFTER REPAIRS ARE MADE OR THE COMPRESSOR WILL NOT COME ON IN COOLING MODE.

F. Fan Cycle Switch

The fan cycle switch is located behind the decorative front cover below the control panel. It is designed to operate the fan either continuously or intermittently with the compressor or heating elements. When the switch is in the CONTINUOUS position, the fan will run continuously at the selected speed when the unit is turned on. With the fan cycle switch in the CYCLE position, the fan will run only when the compressor or heating elements cycle on.

NOTE: It is recommended that this switch be set in the continuous position for maximum comfort and temperature control.

G. Fresh Air Vent Control

The vent control lever is located behind the front cover on the left side of the unit. The unit is shipped in the closed position with a locking screw in place. The screw must be removed to operate the lever. When the lever is back, (OPEN), outside air is mixed with indoor air. When the lever is forward, (CLOSED), no outside air is admitted into the room and room air is recycled through the unit.

NOTE: The vent should remain closed for peak operating efficiency.

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