Ingersoll-Rand Thermo King CRR DF MPC2000, Руководство по обслуживанию

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Operating Instructions
49
Receiver Tank Sight Glass:
A sight glass on the receiver tank contains three small balls that indicate the
level of refrigerant in the tank for checking the refrigerant charge. A moisture indicator in the sight glass
changes color to indicate the level of moisture in the system. Check the color of the indicator against the
color decal in the sight glass. The dry eye in the sight glass is LIGHT GREEN when the system is dry and
YELLOW when the system is wet (contains excessive moisture).
Fusible Plug For High Pressure Relief:
A fusible plug is installed in the R-134a receiver tank to avoid
excessive pressure build-up within the refrigeration system from extraordinary and unforeseen
circumstances. The plug blows when the plug temperature reaches 100 C (212 F). The plug is located so
that refrigerant pressure expelled from the valve would be directed away from anyone servicing the unit.
The plug is non-repairable and requires no adjustment. If the plug blows, recover the remaining
refrigerant charge and replace the fusible plug.
Compressor Oil Sight Glass:
A compressor oil sight glass indicates the relative level of compressor oil in
the compressor sump.
R-23 Refrigeration System Controls, Instruments and Protection
Devices
Compressor Discharge Line Temperature Sensor:
The controller uses the compressor discharge line
temperature sensor to protect the compressor from excessively high operating temperatures. If the
discharge gas temperature rises above 138 C (280 F):
• Unit stops immediately; controller activates Alarm LED and records Alarm 56, Compressor
Temperature Too High.
• Controller will restart the unit when the sensor temperature is below 138 C (280 F).
High Pressure Cutout (HPCO) Switch:
If the compressor discharge pressure rises above 3250 ± 50 kPa,
32.5 ± 0.5 bar, 470 ± 7 psig, the high pressure cutout opens to interrupt the ground circuit to the
compressor contactor:
• R-23 compressor STOPS immediately.
• Evaporator and condenser fans and R-134a compressor continue normal operation.
• R-23 compressor will restart when the overload condition is corrected (switch closes) as long as
power is available. The high pressure switch resets (closes) when the pressure drops to 2590 ± 250
kPa, 25.9 ± 2.5 bar, 375 ± 38 psig.
NOTE: R 23 protective device auxiliary contractor mounted on R 134a contractor must supply
digital signal to MBR J12 pin 1 and 2 before R 23 compressor is allowed to start.
Suction Pressure Gauge:
A suction pressure gauge indicates the refrigerant pressure in the suction line
returning to the compressor.
Discharge Pressure Gauge:
A discharge pressure gauge indicates the refrigerant pressure in the discharge
line leaving the compressor.
Receiver Tank Sight Glass:
Two sight glasses on the R-23 receiver tank contains three small balls that
indicate the level of refrigerant in the tank for checking the refrigerant charge. A moisture indicator in the
sight glass changes color to indicate the level of moisture in the system. Check the color of the indicator
against the color decal in the sight glass. The dry eye in the sight glass is LIGHT GREEN when the
system is dry and YELLOW when the system is wet (contains excessive moisture).
Compressor Oil Sight Glass:
A compressor oil sight glass indicates the relative level of compressor oil in
the compressor sump.