Daikin GYEQ20AN, Руководство по обслуживанию

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Inspecting the Outdoor Unit SiAUY361411EA
197 Parts Inspection
1.31 Inspecting the Four-way Valve
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Output voltage
1. Using a tester, check if the output voltage requirements specified above are met.
2. If the voltage is significantly different than specified above, stop the system using the
onboard checker and wait for 5 minutes; then, with the power OFF, check the harness for
continuity and the junction connector for contact failure using a tester.
3. If the harnesses and connectors are OK, then check each component.
„
Inspecting the four-way valve coil
Inspect the four-way valve coil by measuring the resistance between its connectors.
1.32 Inspecting the SC Coil
While the system is running, inspect the SC coil contained in the receiver as follows:
1. Check if the number of pulses from EV4 is 5.
(Use the onboard checker's channel 10.)
2. Calculate SH using the formula:
SHS4 = intake air temperature 4 (CH28) - temperature equivalent temperature (CH55)
3. If SHS4 is approximately 0 with EV4 transmitting 5 pulses, chances are that EV4 or the SC
coil is broken.
4. Measure the temperature at points T1, T2, and T3 indicated in the figure at right.
If T1 is approximately equal to T2 and T3 is smaller than T2 minus 5 with EV4 transmitting 5
pulses, chances are that the SC coil is broken.
If T2 is smaller than T1 minus 5 with EV4 transmitting 5 pulses, chances are that EV4 is
broken.
∗
This model is slightly different from other models, but there is no significant difference
regarding the measuring points.
Parts to inspect Measuring points
With actuator check
ON
Four-way valve (normal heating)
Between power supply circuit
board's CN112-1 and -3
CH12
200 V AC
Measuring points Measured value
Between connectors 1.2 k
Ω
EV1
EV4
T1
T2
T3
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