Carrier Packaged Terminal s & Heat Pumps 52P - Manual (Page 46)

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WIRING DIAGRAMS (52P AND 52C) (cont)
TYPICAL THERMOSTAT INTERFACE
1. If ‘W’ is ON, then ‘FR’ is forced ON (regardless of ‘G’) and ‘CR’ is forced OFF.
2. If ‘Y’ is ON, then ‘FR’ is forced ON (regardless of ‘G’).
3. If IFT (indoor coil) is < 20° F, then ‘CR’ is forced OFF until IFT is > 50° F.
T’STAT OUTPUT: RC CONTROLER OUTPUT: UNIT OPERATION:
‘G’ — 24 VAC
‘G’ — 0 VAC ‘FR’ — LINE VAC
‘FR’ — 0 VAC
FAN
‘Y’ — 24 VAC
‘O’ — 0 VAC ‘HR1 and HR2’ — LINE VAC
‘RVR’ — LINE VAC
HEATING
‘W’ — 24 VAC ‘HR1 and HR2’ — LINE VAC HEATING
‘Y’ — 24 VAC
‘O’ — 24 VAC ‘CR’ — LINE VAC
‘RVR’ — 0 VAC
COOLING
‘R’ — 24 VAC
‘C’ — COMMON ‘R’ — 24 VAC OUTPUT
‘C’ — COMMON POWER TO WALL
THERMOSTAT
COMPONENT LEGEND
Component Connection (Marked) FM — Fan Motor ST — Start Thermistor
Component Connection (Unmarked) HTR — Heater TRANS — Transformer
Terminal Board Connection IFT — Indoor Frost Thermostat PCBD — Printed Circuit Board
Field Splice NEC — National Electric Code — HR1 — Heater Relay
Field Control Wiring OFT — Outdoor Frost Thermostat — HR2 — Heater Relay
Accessory or Optional Wiring OL — Overload — CR — Compressor Relay
To Indicate Common Potential Only Not To Represent Wire PLS — Primary Limit Switch — FR — Fan Relay
CAP — Capacitor RVS — Reversing Valve Solenoid — RVR — Reversing Valve Relay
COMP — Compressor SLS — Secondary Limit Switch
SSS — Speed Selector Switch
NOTES:
1. Recommended for use on
grounded power supply only.
2. Compressor and fan motor
thermally protected.
3. Use copper conductors only.
4. All wiring must conform with
NEC and local codes.
5. Dashed lines indicate compo-
nents when used.
6. Field control wire suitable for
NEC class 2 control circuit, at
24 volts.
7. OFT determines whether to
bring on compressor heat or
electric heat.
52PQ and 52CQ — Typical Wiring Schematic for Wall Thermostat Control Heat Pump Units