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

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Operating Instructions
50
High Pressure Relief Valve:
A high pressure relief valve is installed in the receiver tank. The relief valve
protects against excessive pressure build-up within the refrigeration system from extraordinary and
unforeseen circumstances. The valve is a spring-loaded piston that lifts when refrigerant pressure exceeds
3447 +520/-104 kPa, 34.47 +5.20/-1.04 bar, 500 +75/-15 psig. The valve is located so that refrigerant
pressure expelled from the valve would be directed away from anyone servicing the unit. The valve will
reset when this pressure drops to 2758 kPa, 27.58 bar, 400 psig. The valve is non-repairable and requires
no adjustment. If the valve fails to reseat properly, recover the refrigerant charge and replace the valve.
Low Pressure Cutout (LPCO) Switch (CRR DF MPC2000ID Units Only):
If the compressor suction pressure
decreases to 0 ± 20 kPa, 0 ± 0.2 bar,6 in. vacuum to 3 psig; the low pressure cutout opens:
• Both the R-23 compressor and R-134a compressor STOP immediately.
• Evaporator and condenser fans continue normal operation.
• R-23 compressor will restart if the low refrigerant condition is corrected (switch closes) as long as
power is available. The low pressure switch resets (closes) when the pressure increases to 70 ± 20
kPa, 0.7 ± 0.2 bar, 10 ± 3 psig.
• When R-23 low pressure switch resets, R-23 compressor restarts 30 seconds after R-134a compressor
restarts.
NOTE: If the low pressure cutout switch remains open, check R-23 system suction and discharge
pressures. Then check for an obstruction or refrigerant leak in the low or high pressure side of the
R-23 refrigeration system.
NOTE: Use only Lower R-23 sight glass to check or add refrigerant on unit unable to maintain -50
to -60 setpoint.
Pretrip Inspection
The following inspections should be made before the container is loaded:
1. Visually check the unit for physical damage.
2. Check the electrical connections in the unit control box, making sure they are fastened securely.
3. Check the conditions of wires and terminals. Repair or replace if necessary.
4. Inspect both refrigeration systems for evidence of oil leaks at all joints and connections.
NOTE: With empty box and all components in R23 system always verify correct charge in R23
system according to pressure readings listed below
5. 5.Check R-23 refrigeration system pressures. Suction and discharge pressure gauges should show
1,600 to 1,800 kPa, 16.0 to 18.0 bar, 232 to 261 psig in both the high and low side with the unit OFF
and the container empty.
6. Check the condenser and evaporator coils. Clean if necessary. Use an air or water spray jet directed
against the coil from the air discharge side. Also inspect the condenser fan grille for damage. If the
grille is damaged or missing, abnormally high head pressure may result. Repair or replace the grille if
necessary.
7. Check the mounting bolts on the unit, compressor and fan motors. Tighten if necessary.
8. Clean the defrost drains.
CAUTION: Air or water spray jet pressure should not be high enough to damage (bend) coil
fins.