Dodge Nitro. Manual — part 759

LOW PRESSURE GAUGE HOSE - The low pressure hose (Blue with Black stripe) attaches to the
low-side service port. This port is located on the A/C suction line near the rear of the engine
compartment.

HIGH PRESSURE GAUGE HOSE - The high pressure hose (Red with Black stripe) attaches to the
high-side service port. This port is located on the A/C liquid line near the front of the engine
compartment.

RECOVERY, RECYCLING, EVACUATION AND CHARGING HOSE - The center manifold hose
(Yellow, or White, with Black stripe) is used to recover, evacuate, and charge the refrigerant system.
When the low or high pressure valves on the manifold gauge set are opened, the refrigerant in the system
will escape through this hose.

REFRIGERANT SYSTEM RECOVERY

Fig. 120: R-134a Refrigerant Recovery/Recycling/Charging Station
Courtesy of CHRYSLER LLC

An R-134a refrigerant recovery/recycling/charging station (1) that meets SAE standard J2210 must be used to

WARNING:

Refer to the applicable warnings and cautions for this system before
performing the following operation. See WARNING, and CAUTION. Failure
to follow the warnings and cautions may result in serious or fatal injury.

2007 Dodge Nitro R/T

2007 HVAC Heating & Air Conditioning - Service Information - Nitro

recover the refrigerant from the R-134a refrigerant system. Refer to the operating instructions supplied by the
equipment manufacturer for the proper care and use of this equipment.

REFRIGERANT SYSTEM CHARGE

After all refrigerant system leaks have been repaired and the refrigerant system has been evacuated, a refrigerant
charge can be injected into the system. See REFRIGERANT CHARGE LEVEL or the Underhood HVAC
Specification Label for the proper amount of the refrigerant charge.

An R-134a refrigerant recovery/recycling/charging station that meets SAE Standard J2210 must be used to
charge the refrigerant system with R-134a refrigerant. Refer to the operating instructions supplied by the
equipment manufacturer for proper care and use of this equipment.

CHARGING PROCEDURE

1. Evacuate the refrigerant system. See REFRIGERANT SYSTEM EVACUATE.

2. Connect an R-134a refrigerant recovery/recycling/charging station that meets SAE standard J2210 to the

refrigerant system.

3. Refer to SPECIFICATIONS or the Underhood HVAC Specification Label for the proper amount of the

refrigerant charge.

4. Measure the proper amount of refrigerant charge and heat it to 52°C (125°F) with the charging station.

See the operating instructions supplied by the equipment manufacturer for proper use of this equipment.

5. Open both the suction and discharge valves, then open the charge valve to allow the heated refrigerant to

flow into the system.

6. When the transfer of refrigerant has stopped, close both the suction and discharge valves.

7. If all of the refrigerant charge did not transfer from the dispensing device, open all of the windows in the

vehicle and set the heating-A/C system controls so that the A/C compressor is engaged and the blower
motor is operating at its lowest speed setting. Run the engine at a steady high idle (about 1400 RPM). If
the A/C compressor does not engage, test the compressor clutch circuits and repair as required.

WARNING:

Refer to the applicable warnings and cautions for this system before
performing the following operation. See WARNING, and CAUTION. Failure
to follow the warnings and cautions could result in possible personal
injury or death.

NOTE:

The Underhood HVAC Specification Label contains the refrigerant fill
specification of the vehicle being serviced.

CAUTION: A small amount of refrigerant oil is removed from the A/C system each

time the refrigerant system is recovered and evacuated. Before charging
the A/C system, you MUST replenish any oil lost during the recovery
process. Refer the equipment manufacturer instructions for more
information.

2007 Dodge Nitro R/T

2007 HVAC Heating & Air Conditioning - Service Information - Nitro

8. Open the low-side valve to allow the remaining refrigerant to transfer to the refrigerant system.

9. Disconnect the charging station from the refrigerant system service ports.

10. Reinstall the caps onto the refrigerant system service ports.

COMPRESSOR-A/C

DESCRIPTION

COMPRESSOR-A/C

Fig. 121: A/C Compressor Components
Courtesy of CHRYSLER LLC

The A/C system on models equipped with the 2.8L and 4.0L engine use a Zexel DKS-17DS A/C compressor
(1). This A/C compressor is a ten cylinder, double-acting swash plate-type compressor that uses an electrically
operated clutch (2) to engage and disengage the A/C compressor from the engine accessory drive belt.

The DKS-17DS A/C compressor has a fixed displacement of 175.5 cubic centimeters (10.7 cubic inches) and
has the suction and discharge ports (6) located on the compressor cylinder block (3). This A/C compressor also
has an integral high pressure relief valve (4) located on the cylinder head (5) and a label which identifies the use
of R-134a refrigerant.

VALVE-HIGH PRESSURE RELIEF-A/C COMPRESSOR

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.

COMPRESSOR-A/C

WARNING:

Take care not to open the discharge (high pressure) valve at this
time. Failure to follow this warning may result in serious or fatal
injury.

2007 Dodge Nitro R/T

2007 HVAC Heating & Air Conditioning - Service Information - Nitro

Fig. 122: A/C Compressor, Discharge Ports & Compressor Cylinder Head
Courtesy of CHRYSLER LLC

The A/C system on models equipped with the 3.7L engine use a Visteon HS-18 A/C compressor (1). This A/C
compressor is a 10 cylinder reciprocating swash plate-type compressor that uses an electrically operated clutch
to engage and disengage the A/C compressor from the engine accessory drive belt.

The HS-18 A/C compressor has a fixed displacement of 180 cubic centimeters (10.9 cubic inches) and has the
suction and discharge ports (2) located on the compressor cylinder head (3) at the rear of the compressor and a
label which identifies the use of R-134a refrigerant.

OPERATION

VALVE-HIGH PRESSURE RELIEF-A/C COMPRESSOR

The high pressure relief valve vents refrigerant from the A/C system when a discharge pressure of 3430 to 3930
kPa (497 to 570 psi) or above is reached. The high pressure relief valve closes with a minimum discharge
pressure of 2990 kPa (4370 psi) is reached.

2007 Dodge Nitro R/T

2007 HVAC Heating & Air Conditioning - Service Information - Nitro