Daikin Perfera RXM R Series Service Manual page 206

4 | Third party components
To check if the refrigerant circuit is correctly charged
Service manual
206
INFORMATION
A bigger temperature drop before and after the expansion valve can be normal,
however excessive ice is indicating a malfunction of the expansion valve or internal
obstruction of the valve (dirt or ice build up in case of humidity in the system).
Temperature drop found?
Yes
No
Due to the relationship to pressure control and electronic expansion valve control,
the amount of refrigerant needs to be examined according to operating conditions.
Refer to the procedures shown below for correct examination.
Refrigerant overcharge diagnosis
1 High pressure rises. Consequently, overload control is conducted to cause
insufficient cooling capacity.
2 The superheated degree of suction gas lowers (or the wet operation is
performed). Consequently, the compressor consumes more power and is
noisy (before over‑current relay trips).
3 The subcooling degree of refriferant in liquid form rises (values >4~5K are NOT
normal).
Cooling
High pressure drooping control
High pressure gradually rises with
increasing operating frequency.
High
pressure
(Low pressure is maintained
Low
at a certain level.)
pressure
Operating
frequency
To maintain low pressure, operating
frequency increases on the capacity control.
(Degree of overcharge)
Proper amount
Action
Replace the clogged part, see
4
procedures" [
Return to the troubleshooting of the
specific error and continue with the
next procedure.
Operating frequency comes to
the lowest level.
Subcooling degree becomes
higher. (The temperature of
liquid connection piping
becomes lower.)
Low pressure rises with lowering
compressor output.
Further overcharge
RXM20~71R + ARXM25~71R + FTXM20~71R + ATXM25~50R +
"Repair
209].
FVXM25~50A
Split New Perfera R32
ESIE20-11 – 2021.01