Outer Fans Control; 4-Way Valve Control; Evaporator Frozen-Preventing Protection Function - Gree Neo GWH09MA-A3DNA3A Installation, Service & Troubleshooting

Product Introduction
Basic Functions - 18K & 24K 230 volt

(2) Outer Fans Control

Notes:
Only the outer fans run for at least 80s in each air flow speed can the air flow be switched; after the outer fans run
compulsively in high speed for 80s when the machine starts up, control the air flow according to the logic. After
remote shutdown, safety stops, and when the machine stops after reaching the temperature point, as well as after the
compressor stops, extend 1 minute, the outer fans will stop (During the period in the 1 minute, the air flow of outer
fans can be changed according to the outdoor ambient temperature changes); when running with force, the outdoor
fans shall run in the highest air flow.

(3) 4-way valve control

1. The 4-way valve control under the modes of Cooling, dehumidification and supplying air: closing;
2. The status of 4-way valve control under the heating mode: getting power;
(1) 4-way valve power control under heating mode a. Starts the machine under heating mode, the 4-way valve will get
power immediately.
(2) 4-way valve power turn-off control under heating mode a. When you should turn off the power or switch to other
mode under heating mode, the power of 4-way valve will be cut after 2 minutes of the compressor stopped. b. When
all kinds of protection stops, the power of 4-way valve will be cut after delaying 4 minutes.
(3) Defrosting control under heating mode: a. Defrosting begins: The power of 4-way valve will be cut after 50s of
entering into the defrosting compressor.
b. Defrosting stops: The 4-way valve will get power after 50s of exiting the defrosting compressor.
(4) Evaporator frozen-preventing protection function At the mode of Cooling, dehumidifying:
Evaporator frozen-preventing protection function is allowed to begin after 6 min of starting the compressor.
1. Starting estimation: After the compressor stopped working for 180s, if Tinner pipe >Tfrozen-preventing frequency-
limited temperature (the temperature of hysteresis is 35.6°F), the machine is only allowed to start for operating,
otherwise it should not be started, and should be stopped to treat according to the frozen-preventing protection: Clear
the trouble under the mode of power turn-off / heating, and the protection times are not counted.
2. Frequency limited
[Tfrozen-preventing normal speed frequency-reducing temperature] ≤ Tinner pipe < [Tfrozen-preventing frequency-
rising of compressor.
limited temperature], you should limit the frequency
3. Reducing frequency at normal speed
If [Tfrozen-preventing high speed frequency-reducing temperature] Tinner pipe < [Tfrozen-preventing normal speed
frequency-reducing temperature] you should adjust the compressor frequency by reducing 8Hz/90s till the lower
limit;
4. Reducing frequency at high speed
If[Tfrozen-preventing power turn-off temperature] ≤Tinner pipe <[Tfrozen-preventing high speed frequency-
reducing temperature] you should adjust the compressor frequency by reducing 30Hz/90s till the lower limit;
5. Power turn-off
If the T inner pipe <[Tfrozen-preventing power turn-off temperature], then frozen-preventing protect to stop the
machine; If
[Tfrozen-preventing frequency-limited temperature ] <T inner pipe, and the compressor has stopped working for 3
minutes, the whole machine should be allowed to operate.
6. If the frozen-preventing protection power turn-off continuously occurs for six times, it should not be resumed
automatically, and you should press the ON/OFF button to resume if the fault keeps on. During the process of
running, if the running time of compressor exceeds the [tevaporator frozen-preventing protection times zero clearing
time], the times of frozen-preventing power turn-off should be cleared to recount. The mode of stopping the machine
or transferring to supply air will clear the trouble times immediately (if the trouble cannot be resumed, mode
transferring will not clear it).
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