52S
SERIES
OPERATING CONTROLS
The controls and components used in the 52S cooling only or heat/cool units are as follows: the selector switch, the indoor thermostat, the dual capacitor, the temperature limiter, the vent lever, and the fan cycle switch (Figure 45).
The selector switch is used to determine the mode of op- eration: 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
It is a mechanical device that restricts the amount of ro- tation of the thermostat. The temperature limiter de- vice may be adjusted by moving the plastic temperature selector tabs to another temperature location on the device. The vent lever is located in the upper right cor- ner of the control box. It is a slide mechanism that opens and closes the vent door. The control may be ac- cessed by removing the front panel of the unit. The fan cycle switch is used to provide 2 options of fan control. The ®rst option, CON, causes the fan to run continuously. The second option, CYC, causes the fan to cycle on when venting, heating, or cooling is requested and off when the thermostat is satis®ed.
The 52S heat pump unit contains all the components of the heat/cool and cooling only unit, and the follow- ing 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 15 F, or at about
30 to 35 F outdoor ambient temperature (about 40 to
45 F outdoor ambient temperature for 1999 models). The unit automatically engages the electric heat strip un- der 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 right side of the unit control box. Placing the over- ride switch into electric heat mode operation will dis- able the compressor for ALL heating or cooling operations.
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.
For 52S remote control (RC) units, all controls are located on the wall mounted thermostat except the vent lever and outdoor thermostat. Remote control is a
See Figure 48 for sample control panels and Figure 49 for controls locations.
FIGURE 45 Ð TYPICAL 52S UNIT
OPERATING CONTROLS
FIGURE 46 Ð MANUAL THERMOSTAT
RCD P/N
FIGURE 47 Ð PROGRAMMABLE THERMOSTAT
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