Panasonic Urban Multi MX1R Series, Service Manual, Page: 34 / 643

PACD011001C2 Function
Function Urban Multi “MX1, ME1 Series” Using R-22 13
A. Compressor M1C / M2C
Connecting a scroll compressor (inverter compressor) that operates on 30~116Hz by inverter drive and a
scroll compressor (standard compressor) that runs on a commercial power supply to the same refrigerant
system enables 21-step capacity control. Capacity control is carried out for individual and linear control of
indoor units.
(M1C: Inverter compressor, M2C: Standard compressor)
C. Check valve
Keeps liquid refrigerant from collecting in the standard compressor when only the inverter compressor is
running.
D. Oil separator
The oil separator is a device that collects the oil discharged from the compressor. The collected oil is
constantly recycled to the compressor via capillary tube.
E. Solenoid valve (hot gas bypass) Y2S
Valve is opened by low pressure safety control when low pressure drops. Balances high/low pressure
when off in order to reduce load when the compressor starts.
F. Outdoor unit electronic expansion valve Y1E
Expansion valve when heating. Senses compressor suction pipe and low pressure equivalent saturated
temperature, and carries out superheat degree control.
G. Solenoid valve (injection) Y3S / Y4S
Controls injection in order to prevent overheating.
Y3S: Inverter compressor, Y4S: Standard compressor
I. Pressure sensor (high pressure, red) SENPH
Semiconductor pressure sensor for sensing the operating status of the indoor by refrigerant pressure which
senses discharge pressure.
J. Pressure sensor (low pressure, blue) SENPL
Semiconductor pressure sensor for sensing the operating status of the indoor by refrigerant pressure which
senses suction pressure.