920-087-04 (3-05)

Desk Control Terminals

The Friedrich PD model PTAC has built-in provisions for connection to an external switch to control power to the unit. The switch can be a central desk control system or even a normally open door switch.

For desk control operation connect one side of the switch to the D1 terminal and the other to the D2 terminal (See figure 13). Whenever the switch closes the unit operation will stop.

Maximum Wire Length for Desk Control Switch

Wire Size

Maximum Length

 

#24

400 ft.

 

#22

600 ft.

Note: The desk

#20

900 ft.

control system and

#18

1500 ft.

switches must be

#16

2000 ft.

field supplied.

Auxiliary Fan Control

The Smart Center also has the ability to control a 24VAC relay to activate an auxiliary, or transfer, fan. The outputs are listed as F1 and F2 on the control board.

To connect the relay, simply wire one side of the relay to F1 and the other side to F2. Anytime that the PTAC fan runs the terminals will send a 24VAC signal to the relay. The relay must be 24 VAC, 50mA or less.

Note: The relay and auxiliary fans must be field supplied.

NOTE: It is the installer's responsibility to ensure that all control wiring connections are made in accordance with the installation instructions. Improper connection of the thermostat control wiring and/or tampering with the unit's internal wiring can void the equipment warranty and may result in property damage, personal injury or death. Other manufacturer's PTACs and even older Friedrich models may have different control wire connections. Questions concerning proper connections to the unit should be directed to the factory.

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.

H. Air Discharge Grille

Moving parts hazard.

Turn off electric power before servicing this component.

Failure to do so can result in property damage, personal injury and/or death.

The air discharge grille can be redirected to blow air either straight up or at an angle into the room. To change the airflow direction, remove the front cover, locate and remove the six grill retaining screws. Reverse the ends of the grille and refasten the grille to the cover.

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Friedrich 920-087-04 (3-05) Fresh Air Vent Control, Air Discharge Grille, Desk Control Terminals, Auxiliary Fan Control