A/C Compressor Pressure Relief Valve
An A/C pressure relief valve (19D644) is incorporated in the compressor manifold and tube to
- relieve unusually high refrigerant system discharge pressure buildups. For specifications regarding operating pressure(s), refer to «CLIMATE CONTROL SYSTEM-GENERAL INFORMATION»(ref-233738) .
- prevent damage to the A/C compressor and other system components.
- avoid total refrigerant loss by closing after the excessive pressure has been relieved.
A/C Condenser Core
Note. Installation of a new 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 A/C condenser core has the following characteristics
- It is an aluminum fin and tube design heat exchanger located in front of the vehicle radiator (8005).
- It cools compressed refrigerant gas by allowing air to pass over the fins and tubes to extract heat and by condensing gas to liquid refrigerant as it is cooled.
A/C Evaporator Core
Note. Installation of a new 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.
Note. The evaporator core is serviced as a core and housing assembly. The evaporator core, internal doors, seals and door linkage are included with the housing.
The A/C evaporator core is the plate/fin type.
- The A/C evaporator core is located inside the vehicle in the evaporator core housing.
- A mixture of refrigerant and oil enters the bottom of the A/C evaporator core through the A/C evaporator core inlet tube and then moves out of the A/C evaporator core through the A/C evaporator core outlet tube.
- During A/C operation, air from the blower motor is cooled and dehumidified as it passes through the evaporator core fins.
Scheme 93
Note. A new A/C evaporator core orifice should be installed whenever a new A/C compressor is installed.
The A/C evaporator core orifice (19D990) has the following characteristics
- It is located in the aft condenser to evaporator 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 A/C evaporator core orifice.
- O-ring seals on the A/C evaporator core orifice prevent the high-pressure liquid refrigerant from bypassing the A/C evaporator core orifice.
- Adjustment or repair cannot be made to the A/C evaporator core orifice assembly. It must be installed as a unit. The evaporator core orifice can be accessed by separating a tube-0 fitting in the condenser to evaporator line. An A/C evaporator core orifice or O-ring seal is not considered a major component but a new A/C evaporator core orifice should be installed whenever a new A/C compressor is installed for lack of performance.
Suction Accumulator
Note. Installation of a new 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.
A new suction accumulator (19C836) should be installed if one of the following conditions exists
- The suction accumulator is perforated.
- There is evidence of moisture in the system such as internal corrosion of metal refrigerant lines or the refrigerant oil is thick and dark. The suction accumulator is mounted to the A/C accumulator bracket (19D606) to the right of the vehicle centerline. The inlet tube of the suction accumulator is attached to the evaporator to accumulator suction line. The outlet tube attaches to the evaporator to compressor suction line (19D742). After entering the inlet of the suction accumulator, 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 low charge protection switch. A long-travel Schrader-type valve system core is installed in the fitting so that the low charge protection switch can be removed without recovering the refrigerant.
Low Charge Protection Switch
The low charge protection switch (19E561) is used to prevent A/C compressor damage in the event of a low refrigerant charge.
- The electrical switch contacts open when the suction pressure drops below normal levels. The contacts close when the suction pressure rises. For specifications regarding operating pressure(s), refer to «CLIMATE CONTROL SYSTEM-GENERAL INFORMATION»(ref-233738) .
- When the low charge protection switch contacts open, the A/C clutch field coil is de-energized and compressor operation stops.
- The low charge protection switch is mounted on a Schrader-type valve fitting on the top of the suction accumulator.
- A valve depressor, located inside the threaded end of the low charge protection switch, presses in on the Schrader valve stem, allowing the suction pressure inside the suction accumulator to control the operation of the low charge protection switch.
- It is not necessary to recover the refrigerant to remove the low charge protection switch.
Dual Function Pressure Switch
The dual function pressure switch (19D594) is used to interrupt A/C compressor operation in the event of high system discharge pressures.
- The dual function pressure switch is mounted on a Schrader-type valve fitting on the compressor manifold and tube assembly.
- It is not necessary to recover the refrigerant when removing the dual function pressure switch.
- A valve depressor, located in the threaded end of the dual function pressure switch, presses on the Schrader-type valve stem. This allows the dual function pressure switch to monitor the compressor discharge pressure.
- When the compressor discharge pressure rises, the switch contacts open, disengaging the A/C compressor. When the compressor discharge pressure drops, the switch contacts close to allow operation of the A/C compressor. For specifications regarding operating pressure(s), refer to «CLIMATE CONTROL SYSTEM-GENERAL INFORMATION»(ref-233738) .
- The dual function pressure switch has a second set of electrical contacts used for high-speed cooling fan control. When the compressor discharge pressure rises, the contacts close and engage the high-speed cooling fan control. When the pressure drops, the contacts open and the high-speed cooling fan control is disengaged. For additional information, refer to «ENGINE COOLING»(ref-233700) .
Scheme 94
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.
- 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 (19E746) may be used to secure the coupling but is not required.
Scheme 95
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.
- When correctly assembled, the male and female fittings should be flush.
- Use only the O-ring seal listed in the Ford Master Parts Catalog.
Scheme 96
When disconnecting or connecting tube-0 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.
Scheme 97
The high-pressure service gauge port valve is located on the high-pressure liquid line.
The low-pressure service gauge port valve is located on the evaporator-to-suction accumulator line.
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.
- A very small amount of leakage will always be detectable around the Schrader-type valve with the A/C charging valve cap removed, and is considered normal. A new Schrader-type valve core can be installed if the seal leaks excessively.
- The A/C charging valve caps are used as primary seals in the refrigerant system to prevent leakage through the Schrader-type valves from reaching the atmosphere. Always install and tighten the A/C charging valve caps (19D702) to the correct torque after they are removed.
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. For additional information, refer to CLIMATE CONTROL SYSTEM-GENERAL INFORMATION .
Refer to CLIMATE CONTROL SYSTEM-GENERAL INFORMATION .
Material
| Item | Specification |
|---|---|
| PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-DA (Motorcraft YN-12-C) | WSH-M1C231-B |
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-DA (Motorcraft YN-12-C) | WSH-M1C231-B |
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
Scheme 98
Scheme 99
Scheme 100
Scheme 101
Scheme 102
Scheme 103
- Remove the condenser to evaporator line (19835). For additional information, refer to «CONDENSER TO EVAPORATOR LINE»(ref-233704-S19607211492006052600000) .
- Pull back the protective cover.
- Index-mark and disconnect the two halves of the condenser to evaporator line. Discard the O-ring seal.
- Inspect the evaporator core orifice (19D990) for damage.
- Engage the special tool with the evaporator core orifice.
- Holding the special tool T-handle stationary, rotate the special tool body to remove the evaporator core orifice.
- Screw the end of the special tool into the broken evaporator core orifice.
- Holding the special tool T-handle stationary, rotate the special tool body to remove the broken evaporator core orifice.
Scheme 104
| Item | Specification |
|---|---|
| PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-DA (Motorcraft YN-12-C) | WSH-M1C231-B |
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-DA (Motorcraft YN-12-C) | WSH-M1C231-B |
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-DA (Motorcraft YN-12-C) | WSH-M1C231-B |
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS
| Item | Specification |
|---|---|
| PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-DA (Motorcraft YN-12-C) | WSH-M1C231-B |
| Refrigerant Compressor Oil (Mineral Oil) F73Z-19577-AA (Motorcraft YN-9-A) | ESH-M2C31-A2 |
MATERIALS