Gree U-MATCH GFH09K3CI, Service Manual

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A/A DC INVERTER U-MATCH AIR CONDITIONERS MAINTENANCE
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2.4Test Points and Testing Method of the Rectifier
3 Status Indicating Lamp of the Electric Control Box of the Outdoor Unit
There are three independent indicating lamps on the electric control box of the outdoor unit, and they will flash
on for five seconds and then black out for another five seconds, which is called a round. Once the lamp blacks out
for more than 1 seconds, it means this round is over and the next round begins as it flashes on again.
2.2.2 Analysis to the Common After-Sales Faults
1. Stalling of the Outdoor Fan Motor
Method of testing the AC fan motor: pull out the terminals of the fan motor, then measure the resistance
between the red, brown, and black wires with the universal meter; the normal resistance is several hundreds ohms,
if not, it indicates there is a open circuit and the fan motor is defective.
If the measured resistance of the fan motor is abnormal, please replace the fan motor; if not, please replace the
control of the outdoor unit.
2. Temperature Sensing Fault
This fault can be confirmed according to the error code displayed on the indoor unit.
Replace the corresponding temperature sensor according to the error code. If possible, pull out the temperature
sensor and measure the resistance between its two ends to see if the it is defective or not.
If the fault still exists afte r the replacement of the temperature sensor, then please replace the electric control
box of the outdoor unit.
3. IPM Protection
（ H5 ）
a.Pull out the power plug for three minutes and then plug it again, in which case, if H5 appears in no time, check
if the terminals of the compressor are improperly connected or loosened; if not, replace the electric control box of the
outdoor unit; if the fault still exists, then it indicates the compressor is defective and should be replaced.
b. When H5 appears after the unit has run for a period of time, then it is necessary to see if the running
environment is really badly (e.g. the condenser is blocked with filth). If not, there is a need of a further check to see if
the wiring of the compressor is reverse, the screws of the module is tightened, or if the compressor is defective etc;
If the fault is beyond the statement above, please replace the electric control box of the outdoor unit.
4. Heating Failure
1. Under the heating status, measure the voltage between two wires of the four-way valve with a universal
meter. The testing points are 4V and AC-L2. If the measured voltage is not about AC230V, then it indicates that the
electric control box of the outdoor unit is defective and should be replaced.
2. If the measured voltage is about AC230V, then cut off the power supply and pull out these two wires of the
four-way valve and measure the resistance between the test points to see if it is about 1-2K. If it is much larger, it
indicates that there is a open circuit among the coils of the four-way valve which then should be replaced.
3. If the coils of the four-way valve is normal, then the failure may be caused by the system abnormity.
5. Cooling Failure
The cooling failure is posed generally when the Relay K5’s contactor of the four-way valve of the outdoor unit’s
electric control box is bonded, and it can be checked out by the universal meter.
2.2.3 Solutions to the Unsolved Faults after the Replacement of the Electric Control Box
1 .After the Replacement of the Electric Control Box of the Outdoor Unit
If the faults still exist after the replacement of the electric control box of the outdoor unit, please take a check to
see if the communication line, temperature sensor, reactor, fan motor, or compressor is normal or not.
Communication line: check if the communication line, live line, or neutral line are connected improperly or the
contactor of the terminals are not good. If the line is extended, then check if the joint is in good condition.