Sinclair AST-24AI, Руководство по обслуживанию

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Service Manual
42
Installation and Maintenance
10. P5: Compressor phase current overcurrent protection
Malfunction description: Compressor operation current is over than the setting protection value.
Main check points:
a. Check if the indoor and outdoor ambient temperature is over than normal cooling, heating temperature range;
b. Check if the evaporator is too dirty that affect the heat exchanging effect.
11. H3: Compressor overload protection
Malfunction description: Temperature of top compressor is over than the limit value
Main check points:
a. Normally the compressor overload protection switch is always on, check if the switch is normal.
12. H5: IPM module protection
Main check points:
a. Check if the compressor wiring connection is well connected, if the compressor wiring sequence is correct. The correct wiring
sequence is yellow, blue, red in anticlockwise direction.
b. Measure if the DC voltage between D10 is around 15V, if it is less than 13.5V or more than 18V, please replace ODU
mainboard.
c. Pull off the compressor connection wire, measure the impedance between phase U/V/W and P/N, if any of them is short
circuit, please replace the ODU mainboard;
d. Check if the compressor is damaged, measure the resistance between any two phases of the compressor three phases.
They should be almost the same, if they’re with big difference, the compressor is damaged, please check the insulation
condition of three phases to the case.
Compressor overload detection terminal
15V positive pole test point--5V negative pole test point
Phase U---phase V--phase W