COMPRESSOR-A/C
DESCRIPTION
A/C COMPRESSOR
NOTE: Denso 10S17 compressor shown. Visteon
HS-18 compressor similar.
The A/C system on models equipped with the 3.7L,
4.7L, 5.7L and 8.3L engines use a Denso 10S17
reciprocating swash plate-type compressor (1). This
A/C compressor has a fixed displacement of 170 cubic
centimeters (10.3 cubic inches).
The A/C system on models equipped with the 5.9L
diesel engine use a Visteon HS-18 A/C compressor.
This A/C compressor is a 10 cylinder reciprocating
swash plate-type compressor with a fixed displace-
ment of 180 cubic centimeters (10.9 cubic inches).
Both A/C compressors have the suction and discharge
ports (2) located on the compressor cylinder head (3)
at the rear of the compressor and have a label identi-
fying the use of R-134a refrigerant.
HIGH PRESSURE RELIEF VALVE
A high pressure relief valve is located on the A/C compressor. This mechanical valve is designed to vent refrigerant
from the A/C system to protect against damage to the A/C compressor and other A/C system components, caused
by condenser air flow restriction or an overcharge of refrigerant.
OPERATION
A/C COMPRESSOR
The A/C compressor is driven by the engine through an electric clutch, drive pulley and belt arrangement. The A/C
compressor is lubricated by refrigerant oil that is circulated throughout the refrigerant system with the refrigerant.
The A/C compressor draws in low-pressure refrigerant vapor from the A/C evaporator through its suction port. It then
compresses the refrigerant into a high-pressure, high-temperature refrigerant vapor, which is then pumped to the
A/C condenser through the compressor discharge port.
The A/C compressor cannot be repaired and, if faulty or damaged, it must be replaced. The compressor clutch,
pulley and bearing assembly, and clutch field coil are available for service. If an internal failure of the A/C compres-
sor has occurred, the A/C accumulator must also be replaced.
HIGH PRESSURE RELIEF VALVE
The high pressure relief valve vents refrigerant from the A/C system when adischarge pressure of 3445 to 4135
kPa (500 to 600 psi) or above is reached. The high pressure relief valve closes with a minimum discharge pressure
of 2756 kPa (400 psi) is reached.
The high pressure relief valve vents only enough refrigerant to reduce theA/C system pressure, and then re-seats
itself. The majority of the refrigerant is conserved in the A/C system. If the high pressure relief valve vents refrig-
erant, it does not mean the valve is faulty.
The high pressure relief valve is factory-calibrated and cannot be adjusted or repaired, and must not be removed or
otherwise disturbed. The valve is only serviced as a part of the A/C compressor.
