Daikin RXM20R Service Manual page 82

4 | Components
To perform a mechanical check of the expansion valve
To perform an electrical check of the expansion valve
Service manual
82
Prerequisite: Power OFF the unit for 3 minutes. Then turn ON the unit and listen to
the expansion valve assembly. If the expansion valve does NOT make a latching
sound, continue with the electrical check of the expansion valve, see
"4.5.1 Checking procedures" [
Prerequisite: Stop the unit operation via the user interface.
Prerequisite: Turn OFF the respective circuit breaker.
Prerequisite: Remove the required plate work, see
1 Remove the expansion valve insulation (if applicable) and visually check:
▪ For oil drops around the expansion valve. Locate and fix as necessary.
▪ Pipes for signs of damage. Replace pipes as needed.
▪ Coil wires for signs of damage. Replace expansion valve coil as needed. See
"4.5.2 Repair procedures" [
2 Remove the expansion valve coil from the expansion valve body, see
"4.5.2 Repair procedures" [
3 Slide the expansion valve magnet over the expansion valve body and gently
rotate the magnet clockwise/counterclockwise to manually close/open the
expansion valve. Listen to check if the valve is closing/opening and manually
close the valve when check is done.
INFORMATION
After the check, remove the magnet from the expansion valve body and install the
expansion valve coil on the expansion valve body. Make sure that the expansion
valve coil is firmly slid onto the expansion valve body.
INFORMATION
It is highly recommended to perform a power reset after checking the valve using a
magnet.
Does the expansion valve open?
Yes
No
1 First perform a mechanical check of the expansion valve, see
4
procedures" [ 81].
2 Disconnect the electrical connector of the expansion valve coil from the
appropriate PCB and measure the resistance of all windings (between the pins
of each phase (wire) and the common wire) using a multi meter. All
measurements MUST be approximately the same.
Name Symbol
Main Y1E
expansion
valve
4
81].
"4.14 Plate
4 85].
4
85].
Action
Perform an electrical check of the
expansion valve, see
procedures" [
Replace the expansion valve body, see
"4.5.2 Repair
Location (PCB) Connector
Main S20
RXM20~71R(9) + ARXM25~71R(9) + FTXM20~71R + ATXM25~50R +
4
work" [ 153].
"4.5.1 Checking
4
81].
4
procedures" [ 85].
"4.5.1 Checking
Winding
resistance
46±4 Ω
FVXM25~50A
Split New Perfera R32
ESIE20-11B – 2022.02