Air Conditioning

AIR CONDITIONING

Refrigerant System Components:

Air Conditioning The A/C refrigerant system is a clutch cycling orifice tube type. The system components are:
- A/C compressor
- A/C compressor clutch field coil
- A/C clutch disc and hub
- condenser core
- evaporator core
- suction accumulator
- connecting refrigerant lines

The refrigeration system operation is controlled by the:
- evaporator core orifice.
- A/C cycling switch.
- A/C pressure relief valve.
- pressure cutoff switch.

The refrigerant system incorporates an A/C compressor controlled by the PCM based on various inputs.

The A/C cycling switch senses evaporator core pressure.

An A/C pressure relief valve is installed in the compressor manifold and tube assembly to protect the refrigerant system against excessively high refrigerant pressures.

An evaporator core orifice is installed in the evaporator core inlet tube to meter the liquid refrigerant into the evaporator core.

A/C Compressor and Clutch Assembly







NOTE:
- Internal A/C compressor components are not serviced separately. The Visteon FS-10 A/C compressor is serviced only as an assembly. The A/C clutch disc and hub, A/C clutch pulley, A/C clutch field coil, and the shaft seal are serviceable.
- Replacement of the suction accumulator is not required when repairing the air conditioning system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the suction accumulator.

The Visteon FS-10 A/C compressor has the following characteristics:
- A ten-cylinder swashplate design utilizing the tangential design mount.
- A one-piece lip-type seal (replaceable from the front of the A/C compressor) is used to seal it at the shaft opening in the assembly.
- Five double-acting pistons operate within the cylinder assembly. The pistons are actuated by a swashplate that changes the rotating action of the shaft to a reciprocating force.
- Reed-type discharge valves are located between the cylinder assembly and the head at each end of the A/C compressor.
- The A/C compressor uses PAG oil or equivalent. This oil contains special additives required for the A/C compressor.
- The A/C compressor oil from vehicles equipped with an FS-10 A/C compressor may have a dark color while maintaining a normal oil viscosity. This is normal for the A/C compressor because carbon from the piston rings will discolor the oil.







The magnetic A/C clutch has the following characteristics:
- It drives the compressor shaft.
- When the battery positive voltage (B+) is applied to the A/C compressor clutch field coil, the clutch disc and hub assembly is drawn toward the A/C clutch pulley.
- The magnetic force locks the clutch disc and hub assembly and the A/C clutch pulley together as one unit, causing the compressor shaft to rotate.
- When B+ is removed from the A/C compressor clutch field coil, springs in the clutch disc and hub assembly move the clutch disc away from the A/C clutch pulley.

A/C Pressure Relief Valve
An A/C pressure relief valve is incorporated in the compressor manifold and tube assembly to:
- relieve unusually high refrigerant system discharge pressure buildups.
- prevent damage to the A/C compressor and other system components.
- avoid total refrigerant loss by closing after the excessive pressure has been relieved.

Condenser Core

NOTE: Replacement of the suction accumulator is not required when repairing the air conditioning system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the suction accumulator.

The condenser core has the following characteristics:
- It is an aluminum fin and tube design heat exchanger located in front of vehicle radiator.
- It cools compressed refrigerant gas by allowing air to pass over fins and tubes to extract heat and by condensing gas to liquid refrigerant as it is cooled.

Refrigerant Lines

NOTE: Replacement of the suction accumulator is not required when repairing the air conditioning system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the suction accumulator.

The condenser-to-evaporator line contains the high-pressure liquid refrigerant upstream of the evaporator core orifice.

The compressor manifold and tube assembly is attached to the A/C compressor and has the following features:
- the upstream side contains low-pressure refrigerant gas.
- the downstream side contains high-pressure refrigerant gas and a fitting used to mount a serviceable high-pressure A/C charge port valve.
- the downstream side also contains a fitting used to mount the pressure cutoff switch. A long-travel Schrader-type valve stem core is installed in the fitting so that the pressure cutoff switch can be removed without discharging the A/C system.

Evaporator Core

NOTE:
- The evaporator core is not separately serviceable. It is serviced only with the evaporator core housing assembly.
- Replacement of the suction accumulator is not required when repairing the air conditioning system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the suction accumulator.

The evaporator core is the plate/fin type.
- A mixture of refrigerant and oil enters the bottom of the evaporator core through the evaporator core inlet tube, and moves out of the evaporator core through the evaporator core outlet tube.
- All airflow from the blower motor passes through the evaporator core and, during A/C operation, is cooled and dehumidified.
- The evaporator core is located in the evaporator core housing at the RH rear of the engine compartment.

Evaporator Core Orifice







NOTE: Install a new evaporator core orifice whenever a new A/C compressor is installed.

The evaporator core orifice has the following characteristics:
- It is located in the evaporator core inlet tube.
- It has filter screens located on the inlet and outlet ends of the tube body.
- The inlet filter screen acts as a strainer for the liquid refrigerant flowing through the evaporator core orifice.
- O-ring seals on the evaporator core orifice prevent the high-pressure liquid refrigerant from bypassing the evaporator core orifice.
- Adjustment or repair cannot be made to the evaporator core orifice assembly. It must be replaced as a unit.

Suction Accumulator







NOTE: Replacement of the suction accumulator is not required when repairing the air conditioning system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the suction accumulator.

The suction accumulator is mounted to the A/C accumulator bracket to the right of the vehicle centerline. The inlet tube of the suction accumulator attaches directly to the evaporator core outlet tube and the outlet tube attaches to the compressor manifold and tube assembly.

After entering the inlet of the suction accumulator, the heavier oil-laden refrigerant contacts an internally mounted dome (which serves as an umbrella) and drips down onto the bottom of the canister.
- A small diameter oil bleed hole, in the bottom of the vapor return tube, allows the accumulated heavier liquid refrigerant and oil mixture to re-enter the compressor suction line at a controlled rate.
- As the heavier mixture passes through the small diameter liquid bleed hole, it has a second chance to vaporize and recirculate through the A/C compressor without causing compressor damage due to slugging.
- A fine mesh screened filter fits tightly around the bottom of the vapor return tube to filter out refrigerant system contaminant particles.
- A desiccant bag is mounted inside the canister to absorb any moisture which may be in the refrigerant system.
- A fitting located on the top of the suction accumulator is used to attach the A/C cycling switch. A long-travel Schrader-type valve stem core is installed in the fitting so that the A/C cycling switch can be removed without discharging the A/C system.

Refrigerant System Dye
Fluorescent refrigerant system dye is added to the refrigerant system at the factory to assist in refrigerant system leak diagnosis using a Rotunda-approved ultraviolet blacklight. It is not necessary to add additional dye to the refrigerant system before diagnosing leaks, even if a significant amount of refrigerant has been removed from the system. Replacement suction accumulators are shipped with a fluorescent dye "wafer" included in the desiccant bag, which will dissolve after approximately 30 minutes of continued A/C operation. It is not necessary to add dye after flushing or filtering the refrigerant system because a new suction accumulator is installed as part of the flushing or filtering procedure. Additional refrigerant system dye should only be added if more than 50% of the refrigerant system lubricant capacity has been lost due to a fitting separation, hose rupture, etc.

A/C Cycling Switch
The A/C cycling switch is mounted on a Schrader valve-type fitting on the top of the suction accumulator.
- A valve depressor, located inside the threaded end of the A/C cycling switch, presses in on the Schrader valve stem.
- This allows the suction pressure inside the suction accumulator to control the operation of the A/C cycling switch.
- The electrical switch contacts open when the suction pressure drops. The contacts close when the suction pressure rises.
- When the A/C cycling switch contacts close, the signal to energize the A/C compressor clutch field coil is sent to the powertrain control module (PCM). The PCM will then actuate the A/C control relay, energizing the A/C compressor.
- When the A/C cycling switch contacts open, the A/C compressor clutch field coil is de-energized and A/C compressor operation stops.
- The A/C cycling switch will control the evaporator core pressure at a point where the plate/fin surface temperature will be maintained slightly above freezing.
- This prevents icing of the evaporator core and blockage of airflow.
- It is not necessary to discharge the refrigerant system to remove the A/C cycling switch.

Pressure Cutoff Switch
The pressure cutoff switch is used to interrupt A/C demand signal to the PCM in the event of high system discharge pressures.
- The pressure cutoff switch is mounted on a Schrader valve-type fitting on the high-pressure side of the compressor manifold and tube assembly (3.0L and 4.0L engines) or the compressor to condenser discharge line (2.3L engine only).
- A valve depressor, located inside the threaded end of the pressure cutoff switch, presses on the Schrader valve stem.
- This allows the pressure cutoff switch to monitor the compressor discharge pressure.
- When the compressor discharge pressure rises the switch contacts open, interrupting the A/C demand signal to the PCM. When the pressure drops the contacts close to complete the A/C demand signal to the PCM.
- It is not necessary to discharge the refrigerant system to remove the pressure cutoff switch.

Spring Lock Coupling







When disconnecting or connecting spring lock couplings, observe the following.
- When the coupling is connected together, the flared end of the female fitting slips behind the garter spring inside the cage of the male fitting.
- The garter spring and cage then prevent the flared end of the female fitting from pulling out of the cage.
- Three O-ring seals are used to seal between the two halves of the couplings.
- Use only the O-ring seals listed in the Ford Master Parts Catalog for the spring lock coupling.
- Lubricate the O-ring seals in clean mineral oil.
- A plastic indicator ring is used to indicate, during vehicle assembly, that the coupling is connected. Once the coupling is connected, the indicator ring is no longer necessary but will remain captive by the coupling near the cage opening.
- The indicator ring may also be used during service operations to indicate connection of the coupling.
- An A/C tube lock coupling clip is used to secure the coupling and is required.

Peanut Fitting







When disconnecting or connecting peanut fittings, observe the following.
- The male and female blocks of the peanut fitting are retained with a nut.
- Support the female fitting with a wrench to prevent twisting of the tubes.
- An O-ring seal is installed around the tube on the male block.
- Lubricate the O-ring seal in clean mineral oil.
- When correctly assembled, the male and female fittings should be flush.
- Use only the O-ring seal listed in the Ford Master Parts Catalog.

Tube-O Fitting







When disconnecting or connecting tube-O fittings, observe the following.
- The male and female portions of the fitting are retained with a nut.
- Support the female fitting with a wrench to prevent twisting of the tubes when disconnecting.
- An O-ring seal is installed around the tube on the male side of the fitting.
- Use only the O-ring seal listed in the Ford Master Parts Catalog.
- Lubricate the O-ring seal in clean mineral oil.

Service Gauge Port Valves
The high-pressure service gauge port valve is located on the compressor manifold and tube assembly (3.0L and 4.0L engines) or the compressor-to-condenser discharge line (2.3L engine only).

The low-pressure service gauge port valve is located on the suction accumulator.







The fitting is an integral part of the refrigerant line or component.
- Special couplings are required for both the high side and low side service gauge ports.
- The Schrader-type valve core can be replaced if the seal leaks.
- Always install the A/C charging valve cap on the service gauge port valves after repairing the refrigerant system.