Gree GRS-1.5/D150ANbA-K, Service Manual

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GREE AIR SOURCE HEAT PUMP WATER HEATER SERVICE MANUAL
58
thermo-bulb fault
F3
、
F4
、
F6
、
Fd
、
FE
、
FL
Check whether the thermo-
bulb is correctly connected.
Check whether the thermo-
bulb resistance exists or
whether the resistance is
normal.
Re-connect the
thermo-bulb.
Replace the
thermo-bulb.
N
N
Y for other options
Y
Replace the mainboard.
3 Repair of Key Components
3.1 Introduction to Key Components
Compressor
Driven by the electric energy, the
compressor compresses refrigerant to
high-temperature and high-pressure gas
and enables the gas to flow circularly in the
refrigerant.
Volume of the low-pressure refrigerant
decreases via compression. After the
pressure
and temperature increases
gradually, it becomes high-pressure and
high-temperature refrigerant, which is the
driving force of the entire system.
Electronic expansion valve
The electronic expansion valve performs
throttling and pressure reduction to
high-pressure liquid refrigerant to ensure
the pressure difference between the
condenser and evaporator.
In addition, it adjusts the flow rate of
refrigerant entering the evaporator based
on heat load change of the evaporator so
as to ensure stable operation of the
refrigeration equipment.
Four-way valve
The four-way valve changes flow direction
of refrigerant during defrosting of the
circular water heater. In the defrosting
mode, the compressed refrigerant enters
the evaporator for heat exchange and
defrosting after its flow direction is changed
by the four-way valve. Then it flows into the
tube heat changer through the expansion
valve. After that, it is sucked by the
compressor to enter the next cycle.