Panasonic Urban Multi MX1R Series Service Manual page 254

PACD011001C2
1.1.5 Function of Thermistors and Pressure Sensors
Outdoor unit
CU-8·10MX1SPP
Capillary
tube
Solenoid
valve
This piping diagram shows the inverter compressor on the left side,
but it is located on the right side on an actual machine.
Stop valve
(With service port on field piping side)
Suction pipe temperature
thermistor (R4T)
Used for superheat
control of electronic
expansion valve when
heating.
Low pressure sensor (SENPL)
When heating:
Used for compressor capacity control and low
pressure safety control by sensing high pressure.
When cooling:
Used for overheating control and low pressure
safety control.
Function Urban Multi "MX1R, ME1R Series" Using R-407C
Filter
Electronic
Filter
expansion
valve
Solenoid Solenoid
valve valve
4-way changeover valve
Capillary tube
Capillary
tube
High
Capillary
pressure
tube
switch
Inverter
comp-
ressor
Pressure sensor
(Low pressure)
Discharge pipe temperature
thermistor
R3-1T (Inverter compressor)
R3-2T (Standard compressor)
Used for compressor discharge
temperature safety.
Fan Fan
Heat exchanger
Pressure
sensor
(High
pressure)
High pressure
switch
Standard
comp-
ressor
Gauge port
Oil temperature thermistor (R5T)
(8, 10 HP only)
(When heating)
1Alters the desired superheat
degree (SH) to prevent wet
operation.
(When defrosting)
1Controls upper limit frequency
to improve dilution of oil.
High pressure sensor (SENPH)
When heating:
Used for compressor
capacity control by sensing
high pressure.
When cooling:
Carries out heat exchange
control during low outdoor
air cooling.
Outdoor temperature
thermistor (R1T)
(When heating)
1Used as the function for
defrost IN conditions.
1OFF by thermostat when
temperature becomes 27
C or higher
Coil temperature thermistor (R2T)
(When cooling)
Not used for anything.
(When heating)
Used together with outdoor
temperature as the function for
defrost IN conditions.
Function
(M008)
233