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52C,P
SERIES
OPERATING CONTROLS
UNIT-MOUNTED CONTROLS
The controls and components used in the 52C,P cool- ing only or heat/cool units are as follows: the selec- tor switch, the indoor thermostat, the dual capacitor, the temperature limiter, the vent lever, and the fan cycle switch. See Figure 37.
The selector switch is used to determine the mode of operation: heat, cool, fan, or off. The indoor thermostat controls the room ambient temperature and cycles the heater or the compressor based on the selector switch setting. The dual capacitor aids in the
INDOOR |
| SELECT0R |
| SWITCH | |
THERMOSTAT |
| |
| 75 | |
| 80 | 70 |
|
|
8565
90 60
TEMPERATURE |
|
LIMITER |
|
| CON |
FAN CYCLE | CYC |
| |
SWITCH |
|
The 52C,P heat pump unit contains all the compo- nents of the heat/cool and cooling only unit, and the following additional ones: the outdoor frost thermostat and the reversing valve. The outdoor frost thermostat prevents operation of the unit in the heat pump mode when the outdoor coil temperature drops below 20 F, or at about 35 F outdoor ambient temperature. The unit automatically engages the electric heat strip and disables the compressor under these conditions.
The outdoor frost thermostat has a manual override to place the unit in electric heat mode operation only. The override switch is located behind the front panel on the front side of the unit control box door.
IMPORTANT: Placing the override switch to elec- tric heat mode operation will disable the compres- sor for ALL heating or cooling operations (for all units except RC units). Placing the override switch to electric heat mode operation on RC units will only disable the compressor in heating mode.
The reversing valve allows for operation in reverse cycle heat pump mode. The valve is located in the piping sys- tem and is controlled by the reversing valve solenoid coil. The coil is energized only during the heating mode.
OUTDOOR FROST THERMOSTAT (HEAT PUMP UNITS ONLY)
FIGURE 37 — 52C,P OPERATING CONTROLS
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