Ford Falcon. Manual — part 308

412-03-5 Air

Conditioning 412-03-5

DESCRIPTION AND OPERATION (Continued)

Climate Control System

Clutch Cycling Orifice Tube Refrigerant System Components (“The refrigerant cycle”)

Item

Description

Item

Description

8

Low pressure low temperature liquid

1

Evaporator thermistor

refrigerant

2

Suction Accumulator assembly

9

Low pressure low temperature refrigerant

3

A/C Orifice Tube

vapour

4

A/C Charge Port (high pressure side)

10

Condenser core

5

A/C Pressure Tranducer

11

Compressor + Clutch assembly

6

High pressure high temperature refrigerant

12

Compressor bracket

vapour

13

A/C charge port (low pressure side)

7

High pressure moderate temperature liquid

14

Evaporator Core

refrigerant

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412-03-6 Air

Conditioning 412-03-6

DESCRIPTION AND OPERATION (Continued)

The A/C refrigerant system is a clutch cycling orifice

The 10S17C A/C compressor has the following

tube type. The system consists of the following

characteristics:

components:

a 10-cylinder swashplate design

A/C compressor/clutch assembly

displacement of 188cc

A/C condenser core

A two-piece lip-type seal is used to seal the shaft

A/C evaporator core

opening in the assembly.

A/C charge port valve (high pressure side)

Five double-acting pistons operate within the

cylinder assembly. The pistons are actuated by a

A/C charge port valve (low pressure side)

swashplate that changes the rotating action of the

connecting refrigerant lines

shaft to a reciprocating force.

suction accumulator

Reed-type discharge valves are located between

The refrigerant system operation is controlled by the

the cylinder assembly and the head at each end

following:

of the A/C compressor.

A/C evaporator core orifice

The A/C compressor uses PAG Compressor Oil

ND-Oil8 or equivalent (meeting Ford specification

A/C cycling switch (evaporator thermistor)

WSH-M1C231-B). This oil contains special

A/C compressor pressure relief valve

additives necessary for the A/C compressor.

A/C pressure cut-off switch (pressure transducer)

The magnetic A/C clutch has the following

The refrigerant system incorporates an A/C

characteristics:

compressor controlled by an A/C cycling switch.

It drives the compressor shaft.

The A/C cycling switch senses A/C evaporator core

When battery positive voltage (B+) is applied to

temperature to control A/C compressor operation.

the A/C clutch field coil, the clutch disc and hub

An A/C compressor pressure relief valve is installed in

assembly is drawn toward the A/C clutch pulley.

the A/C discharge hose assembly to protect the

The magnetic force locks the clutch disc and hub

refrigerant system against excessively high refrigerant

assembly and the A/C clutch pulley together as

pressures.

one unit, causing the compressor shaft to rotate.

An A/C evaporator core orifice is installed in the

When B+ is removed from the A/C clutch field

condenser to evaporator line (A/C liquid line) to meter

coil, springs in the clutch disc and hub assembly

the liquid refrigerant into the A/C evaporator core.

move the clutch disc away from the A/C clutch

pulley.

A/C Compressor and Clutch Assembly

A/C Compressor Pressure Relief Valve

An A/C compressor pressure relief valve is

incorporated in the compressor A/C body to:

relieve unusually high refrigerant system

discharge pressure buildups of (3.43MPa [497

psi] and above).
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

The A/C condenser core has the following

characteristics:

NOTE: Internal A/C compressor & compressor clutch

It is an aluminum fin-and-tube design heat

components are not repaired separately. Install a new

exchanger located in front of the vehicle radiator.

A/C compressor only as an assembly.

It cools compressed refrigerant gas by allowing air

NOTE: Installation of a new suction accumulator is

to pass over the fins and tubes to extract heat and

required when repairing the air conditioning system

by condensing gas to liquid refrigerant as it is

when there is physical evidence of system

cooled.

contamination from a failed A/C compressor, damage

to the suction accumulator, evidence of the A/C

system being open to the atmosphere/leaking or

evidence of moisture absorption.

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412-03-7 Air

Conditioning 412-03-7

DESCRIPTION AND OPERATION (Continued)

Refrigerant Lines

A/C Evaporator Core

NOTE: Installation of a new suction accumulator is

required when repairing the air conditioning system

when there is physical evidence of system

contamination from a failed A/C compressor, damage

to the suction accumulator, evidence of the A/C

system being open to the atmosphere/leaking or

evidence of moisture absorption.

The condenser to evaporator line (A/C liquid line)

contains high pressure liquid refrigerant upstream of

the A/C evaporator core orifice. This orifice tube can

be serviced by disconnecting liquid line from the body

and undoing the nut joining both halves of the liquid

line. The liquid line incorporates a high pressure

charge port valve which is only used in the vehicle

assembly plant.

The A/C HVAC assembly contains the A/C evaporator

The condenser inlet hose (discharge hose) contains

core. The A/C evaporator core is the plate/fin type

high temperature high pressure refrigerant vapour.

with a unique refrigerant flow path.

This discharge hose incorporates an A/C pressure

A mixture of refrigerant and oil enters the evaporator

cut-off switch (pressure transducer) which disables

core through the A/C evaporator core inlet tube and is

the compressor in the event of excessively high or low

routed so it flows through the core tubes and

system pressures, and selects low or high condenser

channels from driver to passenger side of the core.

fan speeds.
The compressor inlet hose (suction hose) contains

low temperature low pressure refrigerant vapour. In

the V8 vehicle, the suction hose is attached to a

suction tube via a quick-connect clamp. For all

models, the suction hose/tube is attached to the

suction accumulator via a quick-connect clamp. The

suction hose incorporates a low pressure charge port

valve which is used for all A/C system servicing.
The BA Falcon 6-cylinder petrol/LPG compressor inlet

hoses (suction hoses) from Feb 2004 have been

standardised (BA-19997-D) and this is different to the

early level of BA Falcon petrol/LPG suction hoses

(BA-19997-A and BA-19997-C), both in the hose

material and routing.
All hose/tube assemblies contain refrigerant O-rings

The Refrigerant Flow path follows the flow shown.

which are retained in a recessed groove. These

O-rings seal against leakage using radial compression

once the joint is fully assembled and further tightening

of the fitting bolt or tube nut will not improve the

sealing performance. These O-rings are black in

colour and made of a special material compatible with

refrigerant and refrigerant oil. Use only black genuine

Ford refrigerant O-rings for replacement.
On the evaporator inlet and outlet tube joints,

green/blue refrigerant O-rings are fitted. Again, these

O-rings are made of a special material compatible

with refrigerant and refrigerant oil, and are different

dimensions to the black refrigerant O-rings. Use only

green/blue genuine Ford refrigerant O-rings for

replacement in these locations.

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412-03-8 Air

Conditioning 412-03-8

DESCRIPTION AND OPERATION (Continued)

The BA Falcon suction accumulator from December

A/C Orifice Tube Assembly

2003 (BA-19C808-B, post December 2003) has a

different mounting to the earlier version of BA Falcon

accumulator (BA-19C808-A, pre December 2003).

Both the later level accumulator bracket and the

welded body apron brackets have been revised, and

the later level accumulator bracket cannot be fitted to

the earlier level body bracket.
The suction accumulator is mounted via the A/C

accumulator bracket onto the LH body apron. The

inlet tube of the suction accumulator is connected to

the A/C evaporator outlet tube. The outlet tube of the

accumulator is connected to the A/C suction

hose/tube assembly.
After entering the inlet of the suction accumulator,

heavier oil-laden refrigerant contacts an internally

mounted dome (which serves as an umbrella) and

NOTE: Install a new A/C orifice tube assembly

drips down onto the bottom of the canister.

whenever a new A/C compressor is installed.

A small diameter oil bleed hole, in the bottom of

NOTE: The red orifice tube can not be interchanged

the vapour return tube, allows the accumulated

with different colour orifice tubes from previous

heavier liquid refrigerant and oil mixture to

models.

re-enter the compressor suction line at a

controlled rate.

The A/C orifice tube has the following characteristics:

As the heavier mixture passes through the small

located at the nut joint in the A/C liquid line

diameter liquid bleed hole, it has a second chance

(condenser to evaporator line).

to vapourise and recirculate through the A/C

color-coded red.

compressor without causing compressor damage

an orifice diameter of ~1.5 - 1.6mm (~0.060in).

due to liquid slugging.

changes the high-pressure liquid refrigerant into a

A fine mesh screened filter fits tightly around the

low-pressure liquid.

bottom of the vapour return tube to filter out

refrigerant system contaminant particles.

filter screens are located on the inlet and outlet

ends of the orifice body

A desiccant bag is mounted inside the canister to

absorb any moisture which may be in the

the inlet filter screen acts as a strainer for the

refrigerant system.

liquid refrigerant flowing through the A/C

evaporator core orifice.

A/C Cycling Switch (evaporator

O-ring seals on the A/C evaporator core orifice

thermistor)

prevent the high-pressure liquid refrigerant from

bypassing the A/C evaporator core orifice.

The evaporator sensor is located on the driver’s side

of the evaporator core towards the lower face of the

Adjustment or repair cannot be made to the A/C

core. The tip of the thermistor contains a sensor which

orifice tube assembly. If damaged or blocked, a

is connected via a harness to the HIM (HVAC

new A/C orifice tube assembly must be installed.

Integrated Module). The sensor is located in an

Refrigerant Dye

optimized position on the core face and controls

compressor “ON”/“OFF” set point as air off

R-134a fluorescent tracer dye has been added to the

temperature changes.

A/C system of this vehicle, supplied in the

The HIM Module changes the set point depending on

accumulator. The refrigerant dye has a limited life of

blower fan speed and thus prevents core ice up.

~500 hours of air conditioning operation.

Varying the fan speed also varies the set point for

Leak checking can be performed with an ultra-violet

cycling the compressor clutch. It is not necessary to

lamp and viewed through ultra-violet glasses.

remove the evaporator core when replacing the

thermistor.

Suction Accumulator

The position of the thermistor in relation to the

NOTE: Installation of a new suction accumulator is

evaporator air off airflow is critical for efficient

required when repairing the air conditioning system

operation of the refrigeration system. It is therefore

when there is physical evidence of system

vital that the correct removal and replacement

contamination from a failed A/C compressor, damage procedure is followed as incorrect positioning of the

to the suction accumulator, evidence of the A/C

thermistor sensor will adversely effect efficiency, and

system being open to the atmosphere/leaking or

could also result in core ice up.

evidence of moisture absorption.

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