Remote Thermostat and Low Voltage Control Connections (Continued)
Thermostat Connections
C | = | Common Ground |
W | = | Call for Heating |
Y | = | Call for Cooling |
R | = | 24V Power from Unit |
GL | = | Call for Fan (Low Speed) |
GH | = | Call for Fan (High Speed) |
B | = | Reversing Valve Energized in heating mode |
*If only one G terminal is present on thermostat, connect to GL for low fan or to GH for high fan operation.
NOTE: It is the installer’s responsibility to ensure that all control wiring connections are made in accordance with the Freidrich installation instructions. Questions concern- ing proper connections to the unit should be directed to the factory:
Desk Control Terminals
The Friedrich
For desk control operation, connect one side of the switch to the D1 terminal and the other to the D2 terminal. 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 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.
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