Gree GRS-1.5/D150ANbA-K, Service Manual

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GREE AIR SOURCE HEAT PUMP WATER HEATER SERVICE MANUAL
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temperature sensor. If the outdoor ambient temperature is not lower than -7°C (0°C of
GRS-1.5/D150ANbA-K
、
GRS-1.5/D200ANbA-K
、
GRS-1.5/TD150ANbA-K
、
GRS-1.5/TD200ANbA-K) and
when no fault is detected and start up conditions of the compressor are met, the system starts by following
the hot water sequence.
(2) Control on fan motor
When start up conditions of the compressor are met, the system starts by following the hot water
sequence. The electronic expansion valve resets and is initialized, and the external fan motor starts. After
10s, the compressor starts. The fan motor will determine whether to still run at high level or to run at low
level based on the ambient temperature after it runs at high level. If the system enters overload control,
the fan motor will switch to discontinuous start up and shutdown status at low level.
(3) Control on defrosting
When the compressor is initially powered on and started, it determines the defrosting condition after
running for the preset duration. If the defrosting condition is met, the system defrosts before running in hot
water mode (including freeze-proofing operation of compressor). After defrosting is over, the compressor
starts for heat up. When the cumulative operation time exceeds or equals to the preset time for defrosting,
defrosting will be performed if the relation between the outdoor exchanger pipe temperature sensor Th
and the outdoor ambient temperature sensor Te meets the defrosting condition.
(4) Control on freeze-proofing function
In the Off state, if water temperature in the water tank detected by the system based on the ambient
temperature is too low, the unit starts the freeze-proofing function immediately.
2 Wired Controller
(1) Controller for GRS-2.4/D270ANbA-K:
1 i-know button 2 Timer button 3 Function button 4 Rapid button
5 Mode button 6 Increase button 7 On/Off button 8 Decrease button