Daikin Sky Air Advance RZA200D7Y1B, Руководство по обслуживанию

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3 | Components
Service manual
70
250D7Y1B
Sky Air Advance-series
ESIE19-13A – 2020.05
5 Wait for the PCB to command the expansion valve to open (pulse output to
expansion valve visible on service monitoring tool).
INFORMATION
If the PCB does NOT command the expansion valve to open (when it is supposed to),
perform a check of the appropriate thermistors and pressure sensors (expansion
valves are driven by superheat or subcool value calculated through the thermistors).
6 While in opening or closing sequence each expansion valve winding (Ф1, 2, 3,
4) is supplied with 12 V DC from the PCB. You will need a good multimeter,
where its range is set to about 20 V DC, and during opening or closing
sequence you may be able to measure the supply voltage for a short time. If
you set the multimeter range to Auto, then most likely you may NOT read a
value between switching ranges. The best way to check is to feel the
movement of the valve by touching, rather than trying to measure the driving
voltage.
7 Check if the expansion valve is open. Check with a contact thermometer (or by
touching) if refrigerant flows through the expansion valve.
Is the expansion valve open? Action
Yes Component is OK. Return to the
troubleshooting of the specific error
and continue with the next step.
No Replace the expansion valve, see
"3.4.2 Repair procedures" [
4
70].
Problem solved?
After all checking procedures listed above have been performed:
Is the problem solved? Action
Yes No further actions required.
No Return to the troubleshooting of the
specific error and continue with the
next procedure.
3.4.2 Repair procedures
To remove the expansion valve motor
Prerequisite: Stop the unit operation via the user interface.
Prerequisite: Turn OFF the respective circuit breaker.
Prerequisite: Remove the required plate work, see "3.12 Plate work" [
4
111].
1 If needed, remove any parts or insulation to create more space for the
removal.