In the heating cycle, the heat anticipator is energized to supply a small amount of heat during the "on" cycle. This will open the contacts in the thermostat prematurely to maintain a closer differential between the "cut in" and "cut out" temperature. The heat anticipator is energized in the heating mode regardless of whether fan is placed in the automatic (MoneySaver) or constant run position.
RANGE: | Cooling Model Thermostat |
| 60°F (±2°) to 92°F (±4°), |
TEST:
Cooling/Heating Models: Remove wires from thermostat and check continuity between terminal "2" (common) and "3" for cooling. Check between terminals "2" (common) and "1" for heating. Also check that contacts in thermostat open after placing in either position. NOTE: Temperature must be within range listed to check thermostat. Refer to the troubleshooting section in this manual for additional information on thermostat testing.
THERMOSTAT ADJUSTMENT
No attempt should be made to adjust thermostat. Due to the sensitivity of the internal mechanism and the sophisticated equipment required to check the calibration, it is suggested that the thermostat be replaced rather than calibrated. Thermostat bulb must be straight to insure proper performance.
Figure 32
Thermostat
Figure 34
Thermostat Bulb Location
(KQ, YQ & SC Models Only)
Thermostat sensor holder 020 to be positioned between the 4th and 5th and 6th and 7th rows of tubes from the bottom of the coil at dimension shown
DEFROST THERMOSTAT (Heat Pump Models Only)
(See Figure 35)
This thermostat is single pole - double throw with contacts between terminals "2" and "3" closing on temperature rise and contacts between terminals "2" and "1" closing on temperature fall. When the contacts between terminals "2" and "1" make, power is supplied to the heater element.
This control is dual purpose control that acts as an outdoor thermostat and defrost control.
When the sensing bulb, attached to the condenser coil, senses enough icing on the outdoor coil, it will interrupt power to the compressor and supply power to the heating element until the coil temperature reaches above 43°, then the heater will shut off and the unit will resume operating in the reverse cycle mode.
When the outdoor coil temperature drops below 20°, the unit will operate in electric heat mode continuously until the outdoor coil temperature rises above 43°.
The fan motor will not turn off when defrost occurs, and the 4- way valve will not reverse.
THERMOSTAT BULB LOCATION
The position of the bulb is important in order for the thermostat to function properly. The bulb of the thermostat should be located approximately 45° to a maximum of 60° from horizontal. Also, do not allow the thermostat bulb to touch the evaporator coil. (See Figures 33 and 34)
Figure 33
Thermostat Bulb Location
(SQ Models Only)
Thermostat sensor holder 020 and anticipator
Figure 35
Defrost Thermostat
(Heat Pump Models)
25
