Abnormal Low Pressure - Daikin RXM20R Service Manual

3.6.6 Abnormal low pressure

RXM20~71R(9) + ARXM25~71R(9) + FTXM20~71R + ATXM25~50R +
FVXM25~50A
Split New Perfera R32
ESIE20-11B – 2022.02
Check item
Is the refrigerant overcharged?
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?
Is there clogging before or after the
expansion valve (capillary)?
Is the check valve (if applicable)
clogged?
Is there a shortage of refrigerant?
In heating 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 check valve (if applicable)
clogged?
3 Troubleshooting
|
Detail
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 if there is a temperature
difference before and after check valve.
If YES, the check valve is clogged.
Conduct refrigerant collection and
vacuum drying, and then add proper
amount refrigerant.
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 if there is a temperature
difference before and after check valve.
If YES, the check valve is clogged.
Service manual
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