Gree GWH09KF-K3DNA5G Service Manual page 25

Service Manual
1.In the case of Tindoor amb. <24°C: if T≤tube40°C and the indoor fan is at stop state, the indoor fan will begin to run at low speed with
a time lag of 2 minutes. Within 2 minutes, if Ttube>40°C, the indoor fan also will run at low speed; and after1-minute operation at low
speed, the indoor fan will be converted tooperation at preset speed. Within 1-minute low speed operation or 2-minute non-operation, if
Ttube>42°C, the fan will run at present speed.
2.In the case of Tindoor amb.≥24°C: if Ttube≤42°C, the indoor fan will run at low speed, and afterone minute, the indoorfan will be
converted to preset speed. Within one-minute low speed operation, if Ttube>42°C, the indoor fan will beconvertedto preset speed.
Note:T indicated in 1 and 2 refers to, under initially heating mode, the indoor ambient temperature before the command to start
indoor amb.
the compressor is performed according to the program, or after the unit is withdrawn from defrost, the indoor ambient temperature
before the defrost symbol is cleared.
●Total current up and frequency down protection
If the total current I ≤W, frequency rise will be allowed; if I ≥X, frequency rise will not be allowed; if I ≥Y, the compressor will run at
total total total
reduced frequency; and if I ≥Z, the compressor will stop and the outdoor fan will stop with a time lag of 30s.
total
(4) Fan Mode
Under the mode, the indoor fan will run at preset speed and the compressor, the outdoor fan, the four-way valve and the electric heater
will stop.
Under the mode, temperature can be set within a range of 16~30°C.
(5) AUTO Mode
① The condition and process of auto
a. When Tamb.≥26°C the unit will operate at Cooling mode. In that case, the set temperature will be 25°C.
b. When Tamb.≤22°C the heat pump unit will operate at Heating mode. In that case, the set temperature will be 20°C; the cooling-only
unit will operate at Fan mode and the set temperature will be 25°C.
c. When 23°C≤Tamb.≤25°C the unit will keep its operation status but if it is firstly energized, the unit will operate at Fan mode.
d. When unit operates at Auto mode, the frequency of compressor will be the same as that in Cooling mode if the unit is coolingwhile it
will be the same as that in the Heating mode if the unit is heating.
② Protection function
a.In cooling operation, protection is the same as that under the cooling mode;
b.In heating operation, protection is the same as that under the heating mode;
c.When ambient temperature changes, operation mode will be converted preferentially. Once started, the compressor will remain
unchanged for at least 6 minutes.
(6) Common Protection Functions and Fault Display under COOL, HEAT, DRY and AUTO Modes
① Overload protection
Ttube: measured temperature of outdoor heat exchanger under cooling mode; and measured temperature of indoor heat exchanger
under heating mode.
1) Cooling overload
a. If T tube52, the unit will return to its original operation state.
b. If T tube55, frequency rise is not allowed.
c. If T tube58, the compressor will run at reduced frequency.
d. If T tube62, the compressor will stop and the indoor fan will run at preset speed.
2) Heating overload
a. If T tube52, the unit will return to its original operation state.
b. If T tube55, frequency rise is not allowed.
c. If T tube58, the compressor will run at reduced frequency.
d. If T tube62, the compressor will stop and the indoor fan will blow residue heat and then stop.
② Exhaust temperature protection of compressor
If exhaust temperature 98, frequency is not allowed to rise.
If exhaust temperature 103, the compressor will run at reduced frequency.
If exhaust temperature 110, the compressor will stop.
If exhaust temperature 90 and the compressor has stayed at stop for at least 3 minutes, the compressor will resume its operation.
③ Communication fault
If the unit fails to receive correct signals for durative 3 minutes, communication fault can be justified and the whole system will stop.
④ Module protection
Under module protection mode, the compressor will stop. When the compressor remains at stop for at least 3 minutes, the compressor
will resume its operation. If module protection occurs six times in succession, the compressor will not be started again.
⑤ Overload protection
If temperature sensed by the overload sensor is over 115, the compressor will stop and the outdoor fan will stop with a time lag of 30
seconds.
⑥ If temperature is below 95, the overload protection will be relieved. If voltage on the DC bus is below 150V or over 420V, the
compressor will stop and the outdoor fan will stop with a time lag of 30 seconds. When voltage on the DC bus returns to its normal
value and the compressor has stayed at stop for at least 3 minutes, the compressor will resume its operation.
Installation and Maintenance
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