Daikin FTXP20-71L Service Manual page 145

To check if the refrigerant circuit is clogged
ATXP20~35 + FTXP20~71 + ARXP20~35 + RXP20~71
Split Comfora R32
ESIE18-01E – 2023.01
The refrigerant circuit stop valves are
open?
No
Prerequisite: Stop the unit operation via the user interface.
Prerequisite: Turn OFF the respective circuit breaker.
1 Wait for the refrigerant to reach the outdoor temperature.
2 Check that all field piping is done according to the refrigeration practice and
installation manual:
▪ Correct piping diameters
▪ Piping distance limits are followed
▪ NO pipes are squeezed
▪ NO short radius bends
3 Connect a manometer to the service port.
4 Turn ON the power of the unit.
5 Activate Heating operation via the user interface.
6 Read the pressure on the pressure gauge. If, at the start of the unit operation,
the pressure is high or very low, the refrigerant circuit might be clogged.
7 On the refrigerant liquid piping (between the indoor unit heat exchanger and
the outdoor unit heat exchanger (coil)), using a contact thermometer,
measure the temperature before and after every restricting device. If a big
temperature difference is measured (>2.5~4K), an internal pipe obstruction
may be present at this location.
INFORMATION
Focus on positions with a potential risk for clogging such as:
▪
Filters
▪
Valves
▪
Brazing points
▪
...
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
4 Third party components
|
Action
Open the stop valves of the refrigerant
circuit, see "4.2.2 Repair
4
procedures" [ 148].
Action
Replace the clogged part, see
"4.2.2 Repair procedures" [
Return to the troubleshooting of the
specific error and continue with the
next procedure.
4
148].
Service manual
145