Ingersoll-Rand 900829, Руководство по обслуживанию

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Refrigeration Service Operations
56
Figure 29: Location of Expansion Valve Bulb
Figure 30: Completely Wrap Bulb with Tape
5. Pressurize the system and test for leaks.
6. Install the evaporator cover.
7. Evacuate and recharge the system.
Low Pressure Cutout Switch
(LPCO)
The low pressure cutout switch is located on a
suction tube in the condenser. If the suction
pressure drops below 5 to 11 in. Hg of vacuum
(-17 to -37 kPa), it opens the LPCO circuit to the
controller to stop the unit.
Low Pressure Cutout Switch Test
1. Install a gauge manifold at the compressor.
2. Disconnect the 2-pin connector with the
LPCO and CHJ wires in main wire harness
from wires to the low pressure cutout switch.
3. Set the thermostat on the lowest setting.
4. Start and run the unit in Cool.
5. Check the continuity between the low pressure
cutout switch wires. The low pressure cutout
switch should be closed when the suction
pressure is above 5 to 11 in. Hg of vacuum
(-17 to -37 kPa). If the suction pressure falls
below 5 to 11 in. Hg of vacuum (-17 to -37
kPa), the low pressure cutout switch should
open.
6. Reconnect the wires that were disconnected
and remove the gauge manifold set when
finished with the test.
Low Pressure Cutout Switch
Replacement
Removal
1. Recover the refrigerant charge.
2. Remove the condenser grille if necessary.
3. Disconnect the wires and remove the switch.
Installation
1. Install and tighten the switch and reconnect
the wires.
2. Pressurize the system and test for leaks.
3. Reinstall the condenser grille (if removed).
4. Evacuate and recharge the system.
Compressor Pressure
Regulator Valve (Model 30 and
50 Only)
The compressor pressure regulator valve is
located in the accumulator module, which is
mounted on the back of the evaporator.