Abnormal High Pressure; Abnormal Low Pressure - Daikin FTXJ-M Service Manual

ESIE16-02K | Part 2. Troubleshooting
Check
Check the expansion valve.

2.3.6. Abnormal high pressure

In cooling mode
Check item
Does the outdoor unit fan run normally?
Is the outdoor unit heat exchanger clogged?
Is there clogging before or after the expansion valve (capillary)?
Is the High Pressure Switch normal?
Is the outdoor unit installed under such conditions that short cir-
cuit easily occurs?
Is the piping length <5 m?
Does air enter the refrigerant system?
Is the refrigerant overcharged?
In heating mode
Check item
Does the indoor unit fan run normally?
Is the indoor unit heat exchanger clogged?
Is the indoor unit installed under such conditions that short circuit
easily occurs?
Is there clogging before or after the expansion valve (capillary)?
Is the High Presure Switch normal?
Is the minimum piping length respected?
Does air enter the refrigerant system?
Is the refrigerant overcharged?

2.3.7. Abnormal low pressure

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.
In cooling mode
Check item
Does the indoor unit fan run normally?
Is the indoor unit heat exchanger clogged?
Is the indoor unit installed under such conditions that short circuit
easily occurs?
Page 46
RA R32 Split & multi split M-Series
Detail
If a passing sound is heard from the pressure reducing valve,
apply sound insulation sheets of putty to reduce the valve noise.
Detail
Visual inspection
Visual inspection
Check if there is a temperature difference before and after
expansion valve (capillary).
Check if the main valve unit of expansion valve operates (by
noise, vibration).
Check continuity by using a tester.
Visual inspection
Visual inspection
Conduct refrigerant collection and vacuum drying, and then add
proper amount refrigerant.
Conduct refrigerant collection and vacuum drying, and then add
proper amount refrigerant.
Detail
Visual inspection
Visual inspection
Visual inspection
Check if there is a temperature difference before and after
expansion valve (capillary).
Check if the main valve unit of expansion valve operates (by
noise, vibration).
Check continuity by using a tester.
Visual inspection
Conduct refrigerant collection and vacuum drying, and then add
proper amount refrigerant.
Conduct refrigerant collection and vacuum drying, and then add
proper amount refrigerant.
Detail
Visual inspection
Visual inspection
Visual inspection
2.3. Symptom based troubleshooting
31/05/21 | Version 1.1