25
10
MUZ-FD50
Sensor
Purpose
Actuator
Compressor
LEV
Outdoor fan
motor
R.V.coil
Indoor fan
motor
Defrost
heater
Discharge temperature
thermistor
Protection
○
○
Indoor coil temperature
thermistor
Cooling : Coil frost prevention
○
Heating : High pressure protec-
tion
○
○
Defrost thermistor
Heating : Defrosting
○
○
○
○
○
Fin temperature thermistor
Protection
○
○
Ambient temperature
thermistor
Cooling : Low ambient tem-
perature operation
○
○
Heating : Defrosting (Heater)
○
Outdoor heat exchanger tem-
perature thermistor
Cooling : Low ambient tem-
perature operation
○
○
Cooling : High pressure protec-
tion
○
○
10-1. CHANGE IN DEFROST SETTING
Changing defrost finish temperature
MUZ-FD25/35
<JS> To change the defrost finish temperature, cut/solder the JS wire of the outdoor inverter P.C. board. (Refer to
11-6-1.)
Jumper wire
Defrost fi nish temperature (
°C
)
JS
Soldered
(Initial setting)
5
None
(Cut)
10
MUZ-FD50
1. Turn OFF the power supply for the air conditioner before making the setting.
2. Set the 4th Dip Switch of SW1 on the outdoor electronic control P.C. board to
ON to change the defrost finish temperature. (Refer to 11-6-2.)
4th Dip Switch of SW1
Defrost fi nish temperature (
°C
)
OFF
(Initial setting)
8.3
ON
12.2
10-2. PRE-HEAT CONTROL SETTING
PRE-HEAT CONTROL
When moisture gets into the refrigerant cycle, it may interfere the start-up of the compressor at low outside temperature.
The pre-heat control prevents this interference. The pre-heat control turns ON when outside temperature is 20°C or
below. When pre-heat control is turned ON, compressor is energized. (About 50 W)
MUZ-FD25/35
<JK> To activate the pre-heat control, cut the JK wire of the inverter P.C. board. (Refer to 11-6.1)
NOTE :
When the inverter P.C. board is replaced, check the Jumper wires,
and cut/solder them if necessary.
MUZ-FD50
[How to activate pre-heat control]
1. Turn OFF the power supply for the air conditioner before making the setting.
2. Set the 2nd Dip Switch of SW1 on the outdoor electronic control P.C. board to
ON to activate pre-heat control function. (Refer to 11-6-2.)
SERVICE FUNCTIONS
SERVICE FUNCTIONS
MUZ-FD25VABH MUZ-FD35VABH MUZ-FD50VABH
1
2
3
4
ON
1
2
3
4
ON
Mitsubishi ilmalämpöpumput huoltaa ja korjaa: Jäähdytinpalvelu RefGroup Oy
www.ilmalämpöpumput.com