Heating Mode - Gree TERRA09HP230V1A Installation, Service & Troubleshooting

Indoor Unit
Heat Exchanger
A. Hot gas is discharged from the compressor. The temperature of the gas in monitored by the Discharge Tem-
perature sensor and sent to the outdoor control panel.
B. The hot gas is directed through the 4-way valve to the indoor coil making the line a hot gas line.
C. The hot gas will enter the indoor coil and condense to a saturated mix as it travel through the coil and will be
slightly subcooled.
D. The refrigerant returns to the outdoor unit through the filter, then trough the EEV reducing the refrigerant
to a low pressure liquid and will maintain 10 degrees F of superheat.
E. The cold refrigerant will travel through the outdoor coil (evaporator) and will pickup heat from the outdoor
air. This will cause the cold saturated refrigerant to flash to a saturated mixture which will be superheated to
10 degrees F.
F. The superheated vapor will travel through the 4-way valve to the accumulator which will prevent liquid
floodback.
G. The superheated gas will enter the compressor for another refrigeration cycle.
The control board will monitor the temperature and pressures and adjust the frequency of the compressor and
flow rate of the EEV as needed. There are no pressure charts to evaluate temperature or pressures.
10
Product Introduction

Heating Mode

Temperature
Sensor
Outdoor Unit
Heat
Filter
Exchanger
Electronic
expansion
valve
Accumulator not
on all sizes
4-way
valve