2. Removing the inverter assembly, inverter P.C. board
(1) Remove the cabinet and panels. (Refer to 1.)(2) Disconnect the lead wire to the reactor and the following con- nectors:
<Inverter P.C. board>
CN721 (R.V. coil)
CN722 (Defrost heater) MUZ-SF25/35/42VEH CN931, CN932 (Fan motor)
CN641 (Defrost thermistor and discharge temperature ther- mistor)
CN643 (Ambient temperature thermistor)
CN644 (Outdoor heat exchanger temperature thermistor) CN724 (LEV)
(3) Remove the compressor connector (CN61).
(4) Remove the screws fixing the heat sink support and the sep- arator.
(5) Remove the fixing screws of the terminal block support and the back panel.
(6) Remove the inverter assembly.
(7) Remove the screw of the earth wire and screw of the termi- nal block support.
(8) Remove the heat sink support from the P.C. board support.
(9) Remove the screw of the inverter P.C. board and remove the inverter P.C. board from the P.C. board support.
Photo 3
Photo 4 (Inverter assembly)
Photo 5 3. Removing R.V. coil
(1) Remove the cabinet and panels. (Refer to 1.) (2) Disconnect the following connectors:
<Inverter P.C. board>
CN721 (R.V. coil) (3) Remove the R.V. coil.
4. Removing the discharge temperature thermistor, defrost thermistor, outdoor heat exchanger tempera- ture thermistor and ambient temperature thermistor
(1) Remove the cabinet and panels. (Refer to 1.)(2) Disconnect the lead wire to the reactor and the following con- nectors:
<Inverter P.C. board>
CN641 (Defrost thermistor and discharge temperature ther- mistor)
CN643 (Ambient temperature thermistor)
CN644 (Outdoor heat exchanger temperature thermistor) (3) Pull out the discharge temperature thermistor from its holder.
(4) Pull out the defrost thermistor from its holder. (Photo 6) (5) Pull out the outdoor heat exchanger temperature thermistor
from its holder. (Photo 6)
(6) Pull out the ambient temperature thermistor from its holder.
Screw of the R.V. coil Screws of the heat sink
support and the separator
Screws of the terminal block support and the back panel
Heat sink
Screw of the earth wire
Screw of the Terminal block support
Screw of the inverter P.C. board
Heat sink support P.C. board
support Terminal
block support Note: As for MUZ-SF25VE(H), the shape of the out-
door heat exchanger is a flat type.
52
OPERATING PROCEDURE PHOTOS
5. Removing outdoor fan motor
(1) Remove the cabinet and panels. (Refer to 1.) (2) Disconnect the following connectors:
<Inverter P.C. board>
CN931, CN932 (Fan motor) (3) Remove the propeller fan nut.
(4) Remove the propeller fan.
(5) Remove the screws fixing the fan motor.
(6) Remove the fan motor.
Photo 6
Photo 7
Photo 8 6. Removing the compressor and 4-way valve
(1) Remove the cabinet and panels. (Refer to 1.) (2) Remove the inverter assembly. (Refer to 2.) (3) Recover gas from the refrigerant circuit.
NOTE: Recover gas from the pipes until the pressure gauge shows 0 kg/cm2 (0 MPa).
(4) Detach the brazed part of the suction and the discharge pipe connected with compressor.
(5) Remove the nuts of compressor legs.
(6) Remove the compressor.
(7) Detach the brazed part of pipes connected with 4-way valve.
Defrost thermistor Outdoor heat exchanger tempera- ture thermistor
Propeller fan nut Screws of the outdoor fan motor
Propeller fan
Brazed parts of 4-way valve
Ambient temperature thermistor
12-2. MUZ-SF50VE MUZ-SF50VEH
NOTE: Turn OFF the power supply before disassembly.
OPERATING PROCEDURE PHOTOS
1. Removing the cabinet
(1) Remove the screws of the service panel.
(2) Remove the screws of the top panel.
(3) Remove the screw of the valve cover.
(4) Remove the service panel.
(5) Remove the top panel.
(6) Remove the valve cover.
(7) Disconnect the power supply and indoor/outdoor connect- ing wire.
(8) Remove the screws of the cabinet.
(9) Remove the cabinet.
(10) Remove the screws of the back panel.
(11) Remove the back panel.
Photo 1
Photo 2
Screws of the cabinet Screws of the top panel
Screws of the top panel
Screw of the back panel Screws of the
cabinet
Screws of the cabinet
Screws of the service panel Screw of
the valve cover
Screws of the cabinet
Screws of the back panel Screws
of the cabinet
54
OPERATING PROCEDURE PHOTOS
2. Removing the inverter assembly, inverter P.C. board
(1) Remove the cabinet and panels. (Refer to 1.)(2) Disconnect the lead wire to the reactor and the following con- nectors:
<Inverter P.C. board>
CN721 (R.V. coil)
CN722 (Defrost heater) MUZ-SF50VEH CN931, CN932 (Fan motor)
CN641 (Defrost thermistor and discharge temperature ther- mistor)
CN643 (Ambient temperature thermistor)
CN644 (Outdoor heat exchanger temperature thermistor) CN724 (LEV)
(3) Remove the compressor connector.
(4) Remove the screw fixing the heat sink support and the sepa- rator.
(5) Remove the fixing screws of the terminal block support and the back panel.
(6) Remove the inverter assembly.
(7) Remove the screw of the earth wire, screw of the P.C. board cover and screws of the terminal block support.
(8) Remove the heat sink support from the P.C. board support.
(9) Remove the screw of the inverter P.C. board and the inverter P.C. board from the P.C. board support.
Photo 3
Photo 4
Photo 5 3. Removing R.V. coil
(1) Remove the cabinet and panels. (Refer to 1.) (2) Disconnect the following connector:
<Inverter P.C. board>
CN721 (R.V. coil) (3) Remove the R.V. coil.
Screw of the heat sink support and the separator
Brazed parts of 4-way valve Screw of the R.V. coil Heat sink
Screw of the inverter P.C. board
Screw of the earth wire
Screws of the terminal block support
Screw of the P.C. board cover Screws of the terminal block support and the back panel
P.C. board support
Heat sink support
OPERATING PROCEDURE PHOTOS
4. Removing the discharge temperature thermistor, defrost thermistor, outdoor heat exchanger tempera- ture thermistor and ambient temperature thermistor
(1) Remove the cabinet and panels. (Refer to 1.)(2) Disconnect the lead wire to the reactor and the following connectors:
<Inverter P.C. board>
CN641 (Defrost thermistor and discharge temperature ther- mistor)
CN643 (Ambient temperature thermistor)
CN644 (Outdoor heat exchanger temperature thermistor) (3) Pull out the discharge temperature thermistor from its hold-
er.
(4) Pull out the defrost thermistor from its holder.
(5) Pull out the outdoor heat exchanger temperature thermistor from its holder.
(6) Pull out the ambient temperature thermistor from its holder.
Photo 6
Photo 7
Photo 8 5. Removing outdoor fan motor
(1) Remove the top panel, cabinet and service panel. (Refer to 1.) (2) Disconnect the following connectors:
<Inverter P.C. board>
CN931 and CN932 (Fan motor) (3) Remove the propeller fan nut.
(4) Remove the propeller fan.
(5) Remove the screws fixing the fan motor.
(6) Remove the fan motor.
6. Removing the compressor and 4-way valve
(1) Remove the top panel, cabinet and service panel. (Refer to 1.) (2) Remove the back panel. (Refer to 1.)
(3) Remove the inverter assembly. (Refer to 2.) (4) Recover gas from the refrigerant circuit.
NOTE:
Recover gas from the pipes until the pressure gauge shows 0 kg/cm2 (0 MPa).(5) Detach the brazed part of the suction and the discharge pipe connected with compressor.
(6) Remove the compressor nuts.
(7) Remove the compressor.
(8) Detach the brazed part of 4-way valve and pipe. (Photo 5)
Screws of the outdoor fan motor
Brazed part of the discharge pipe
Discharge temperature thermistor
Outdoor heat exchanger tempera-
ture thermistor Ambient tem- perature thermistor
Defrost thermistor
Propeller fan nut