TechPlus ComfortAire, Руководство по дополнительному обслуживанию

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Gauge Pressure Related Troubleshooting
Normal compressor suction (low side) and discharge (high side) pressures at
ambient temperature of 86 – 95 degrees F (30 – 38 degrees C) and
compressor speed of approximately 3300 rpm are:
High Pressure: 210 – 300 psi
Low Pressure: 15 – 33 psi
As a rule of thumb the high side pressure will be around 8 times greater than
the low side pressure.
Possible Cause Inspection Solution
Low Pressure side too high. The low pressure side
normally becomes too high
when the high pressure side is
too high. As this is explained
below, the following inspection
is only used when the low
pressure side is too high.
1. Expansion valve opens too
far.
Frost is present on the suction
hose.
Replace expansion valve
2. Defective compressor. The high and low pressure
side gauge equalize when the
magnetic clutch is disengaged.
Replace the compressor.
Low pressure side too low
1. Low refrigerant charge The high side pressure will be
low and bubbles may be
present in the sight glass on
the receiver drier
Repair any leaks and recharge
the refrigerant to the correct
level
2. Restriction between drier
and the expansion valve.
Frost on the line between drier
and the expansion valve. A
negative low pressure reading
may be shown.
Flush system or replace hose.
3. Thermostat malfunction The evaporator is frozen Adjust probe placement, or
replace thermostat
High Pressure too high
1. Poor condenser
performance
Dirt or clogged condenser fins Clean Fins
2. Excessive refrigerant The high pressure side will be
too high, above 325 psi
Use refrigerant recovery
equipment to capture excess
refrigerant. Charge to the
correct level.
3. Excessive oil The high pressure side will be
too high
Evacuate system. Remove the
oil from the compressor and
the condenser. Measure oil
from compressor and add
correct oil charge back to
compressor. Flush system
with nitrogen. Replace drier.
4. Air in system Pressure is high on both high
and low sides
Evacuate and recharge with
refrigerant
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APPENDIX
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