INDOOR |
| ||
COIL | THERMAL EXPANSION | OUTDOOR | |
| THERMAL EXPANSION | ||
| VALVE FOR HEATING | COIL | |
| VALVE FOR COOLING | ||
| (5°F SUPER HEAT) |
| |
| (10°F SUPER HEAT) |
| |
|
|
|
FILTER DRIERS
CHECK
VALVE
| ||
BRAZED | LIQUID LINE | |
REVERSING | ||
CONNECTIONS | ||
| VALVE WITH | |
| ||
| SOLENOID | |
| ||
| VAPOR LINE |
KEY
COOLING CYCLE FLOW
HEATING CYCLE FLOW
SERVICE VALVES WITH
COPPER STUB CONNECTIONS
COMPRESSOR SUCTION LINE
ACCUMULATOR
FIG. 6 - REFRIGERANT FLOW DIAGRAM
OPERATION
GENERAL
During the cooling cycle, when the reversing valve solenoids becomes energized, operation will be the same as any conven- tional air conditioning system.
During the heating cycle, when the reversing valve solenoids becomes
Refer to Figure 6 for illustration showing the flow of refrigerant through a heat pump system.
CAUTION: Reversing valves and check valves are precise mechanical devices and will not tolerate any me- chanical abuse such as hammering. If a refrigerant system isn't properly cleaned after a compressor
SYSTEM SEQUENCE OF OPERATION
The following sequences of operation are based on using the manual changeover thermostat. Refer to the respective unit wiring diagram.
COOLING OPERATION
The following controls will be1. energized through terminal O on the thermostat to put the system in the cooling mode.
•Relays RY3, RY4, RY5, and RY6
If the fan switch on the thermostat2. is in the “ON” position, in- door section blower motor contactor 10M will be energized through terminal G to provide continuous blower operation. If the switch is in the “AUTO” position, the blower will oper- ate only when the thermostat calls for cooling operation.
3.When TC1 of the thermostat closes on demand for cooling, a circuit is made from the Y terminal on DC1 and DC2
Unitary Products Group | 11 |
