Gree GWH09UB-K6DNA4A Service Manual page 36

Service Manual
Outdoor unit
1. System function
1.1 Cooling mode
1.1.1 Working condition and process for cooling
When the compressor is at off status, turn on the unit under cooling mode. When indoor unit reaches the condition of turning on the
unit, the unit operates under cooling mode.Meanwhile, indoor fan, outdoor fan and compressor stops operation.
1.1.2 Stop operation under cooling mode
Compressor stopped operation, compressor stops operation immediately and outdoor fan delay 30s to stop operation.
1.1.3 Switch to heating mode from cooling mode
When switching to heating mode, 4-way will delay 3min to be energized after compressor is stopped. Others are same with that
stopped operation under cooling mode.
1.1.4 4-way valve: 4-way valve will be closed under this mode
1.1.5 Outdoor fan control under cooling mode
After compressor stops operation, outdoor fan will operate at current fan speed for another 30s and then stops operation.
1.2 Drying mode
1.2.1 Working condition and process for drying mode: same with that for cooling mode
1.2.2 Status of 4-way valve: OFF.
1.2.3 Temperature setting range: 16~30°C.
1.2.4 Protection function: Same with that under cooling mode.
1.2.5 The startup condition for electronic expansion valve, outdoor fan and compressor is same as that for cooling mode.
1.3 Heating mode
1.3.1 Working condition and process for heating mode
When indoor unit reaches the startup condition of heating, indoor unit will operate under heating mode.
1.3.2 Stop operation under heating mode:
a. When indoor unit reached OFF or stop operation conditioner, compressor stop operation, and outdoor fan will delay 1min to
stop operation.
b. Switch to cooling(drying) or fan mode
(a) compressor stops operation; (b) 4-way valve will delay 2min to be de-energized;
(c) outdoor fan will delayed 30s to stop operation; (d) status of 4-wayvalve: energized.
1.3.3 Outdoor fan control under heating mode
When compressor stops operation, outdoor fan will delay 30s to stop operation.
1.3.4 Defrosting function
When it satisfied defrosting condition, compressor stops operation. After compressor stoped for 30s, outdoor fan stops operation
and 4-way valve will change direction; After 4-way valve chaging direction, compressor will be startup, defrosting will start counting
time and compressor frquency will be increased to defrosting frequency.
1.4 Fan mode
1.4.1 Compressor, outdoor fan and 4-way valve will all be stopped or closed.
1.4.2 Temperature setting range is 16~30°C.
2. Protection function
2.1 Overload protection function
During cooling mode, measure the temperature of outdoor heat exchanger; during heating mode, measure the temperature of
indoor heat exchanger.
(1)When Ttube≤T1, resume original operation status;
(2)When Ttube≥T2, prohibit increasing frequency;
(3)When Ttube≥T3, compressor will decrease frequency to operate.
(4)When Ttube≥T4, compressor stops operation;
During cooling or drying mode: T1=52; T2=55; T3=58; T4=62;
During heating mode: T1=50; T2=53; T3=56; T4=60;
Under auto heating or heating mode, indoor unit will stop operation after blow residual heat. Under other modes, indoor fan
operates at set fan speed.
Technical Information
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