Daikin SkyAir RZQ200 · 250C7Y1B Service Manual page 186

SiBE26-701
Check No. 4 If the low pressure is abnormally low
Conception
Abnormally low pressure level is mostly caused by the evaporator side.
The following contents are provided based on field checking of service engineer.
Further, the number is listed in the order of degree of influence.
a. In cooling operation
Check items (Possible causes)
1. Does the outdoor unit fan run normally?
2. Is the indoor unit filter clogged?
3. Is there clogging before or after the EV
4. Is the check valve clogged?
5. Is the LPS normal?
6. Is the indoor unit installed under such
7. Is the refrigerant gas short?
a. In heating operation
Check items (Possible causes)
1. Does the outdoor unit fan run normally?
2. Is the outdoor unit heat exchanger
3. Is the outdoor unit installed under such
4. Is there clogging before or after the EV
5. Is the check valve clogged?
6. Is the LPS normal?
7. Is the refrigerant gas short?
Troubleshooting
(capillary)?
conditions that short circuit easily
occurs?
clogged?
conditions that short circuit easily
occurs?
(capillary)?
Diagnosis by Remote Controller
Judgment
1. Visual inspection
2. Visual inspection
3. Check if there is a temperature
difference before and after EV
(capillary).
Check if the main valve unit of EV
operates (by noise, vibration).
4. Check if there is a temperature
difference before and after check valve.
→
If YES, the check valve is caught.
5. Check continuity using a tester.
6. Visual inspection
7. Conduct refrigerant collection and
vacuum drying, and then add proper
amount refrigerant.
Judgment
1. Visual inspection
2. Visual inspection
3. Visual inspection
4. Check if there is a temperature
difference before and after EV
(capillary).
Check if the main valve unit of EV
operates (by noise, vibration).
5. Check if there is a temperature
difference before and after check valve.
→
If YES, the check valve is caught.
6. Check continuity using a tester.
7. Conduct refrigerant collection and
vacuum drying, and then add proper
amount refrigerant.
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