Home/Audi/A6/Audi A6 C5 (1997-2001)/Repair manual/Air Conditioning/Discharging

Contents

Wiring diagrams Section: Air Conditioning

A/C system, safety precautions

A/C system, general repair guidelines

Commercial designation

Color

Airborne properties

Solubility of refrigerant oil

Effects on the environment

Toxicity

Temperature/pressure relationship

Effects on plastics

Effects on metal

Critical temperature/critical pressure

Water solubility

Flammability

Refrigerant containers

Leak detection

A/C refrigerant oil (PAG), properties

Refrigerant system with restrictor and accumulator

A/C compressor

A/C condenser

Evaporator

Accumulator

O-rings

Hoses and lines

Pressure relief valve

A/C system, switches and valve connections

A/C pressure switch -F129

Valve connection for pressure switch

A/C compressor speed sensor -G111

A/C system, quick coupling connections

Connection with Schrader valve (example)

A/C refrigerant system, pressure and temperature relationships

A/C system with restrictor and accumulator, refrigerant flow

Table of pressure and temperature relationships

Refrigerant circuit, servicing

Compressor, with A/C clutch -N25

Compressor, with A/C compressor regulator valve -N280

A/C clutch -N25-, servicing (Denso compressor)

Loosen and tighten hex bolt

Removing clutch plate

Installing magnetic coil

High pressure sensor -G65-, removing and installing

Check function

O-ring seals for refrigerant circuit

A/C system components (in engine compartment)

Evaporator housing drain valve, checking, removing and installing

Air extraction vent, checking

Dust and pollen filter element, removing and installing

Dust and pollen filter with active carbon filter element

Sensor for air quality -G238-, removing and installing

Removing and installing

A/C system components (in passenger compartment)

A/C control head -E87-, removing and installing

Removing and installing, Vehicles without Radio Navigation system

Removing and installing, Vehicles with Radio Navigation system

Control module for fresh air blower -J126-, removing and installing

Fresh air blower -V2-, removing and installing

Sender for outlet temperature, floor outlet -G192-, removing and installing

Left vent temperature sensor -G150-, removing and installing

Right vent temperature sensor -G151-, removing and installing

Evaporator vent temperature sensor -G263-, removing and installing

Fresh air intake duct temperature sensor -G89-, removing and installing

Sunlight photo sensor -G107-, removing and installing

Defroster flap motor -V107-, removing and installing

Notes for installation

Actuator for temperature flap right -V159-, removing and installing

Central air flap motor -V70-, removing and installing

Air flow flap motor -V71-, removing and installing (vehicles up to model year 2002)

Notes on installation

Recirculation flap motor -V113-, removing and installing (vehicles from model year 2002)

Instrument panel vent removal tool, making

Center instrument panel vent, removing and installing

Left instrument panel vent, removing and installing

Right instrument panel vent, removing and installing

Left and right side window defroster vents, removing and installing

Heater core, removing and installing

Removing heater core

Installing heater core

Changes implemented from June 1998

Changes implemented from model year 2002

Air distribution in air conditioner

Air ducts in vehicle interior

A/C system cooling performance, testing

Test requirements

Preparatory steps

Cooling performance checking (vehicles from model year 2002)

Notes

Continuation for vehicles with compressor using A/C Clutch -N25

Identifying malfunctions at temperature increase behind condenser

A/C refrigerant system, leak testing

A/C refrigerant system, testing with pressure gauges

Measuring pressure and temperature in a "switched-on" refrigerant system

Measuring pressure and temperature in a closed container or "switched-off" refrigerant system

A/C refrigerant system, checking pressures

Preparation work

Checking

If A/C refrigerant system base pressure is less than specified on chart, system is low on refrigerant

If A/C refrigerant system pressure corresponds to or is higher than base pressure specified on chart

Pressure in A/C system corresponds to chart or is higher

A/C refrigerant system (R-134a), discharging

Discharging

A/C refrigerant system (R-134a), evacuating and recharging

Evacuating and recharging

A/C refrigerant system (R-134a), flushing with compressed air and nitrogen

A/C refrigerant system, servicing

Determining dimensions of flat tubes from condenser

Restrictor version

Released refrigerant oil (PAG)

Vehicles with compressors with A/C clutch -N25

Refrigerant lines from Denso compressor (with A/C clutch -N25-), removing and installing

Denso compressor, removing and installing from bracket (8 cyl. engine with A/C clutch - N25-)

Removing

Compressor (with A/C Clutch -N25-), removing and installing

Vehicles with compressor drive via a belt

Compressor (installed on right side of engine), removing and installing from bracket

Compressor (installed on left side of engine), removing and installing from bracket

Audi Allroad with 8 cyl. engine (compressor drive via a drive shaft)

Belt pulley, replacing

Pulley, removing from compressor and installing

Compressor drive unit, checking, replacing

Compressor drive shaft, loosening and tightening

Drive shaft, loosening

Drive shaft, tightening

Installing

Drive plate with overload protection, removing and installing

Drive plate to compressor, removing and installing

Drive plate with roller bearing, removing and installing

A/C refrigerant circuit, servicing (compressor with A/C compressor regulator valve -N280-)

Condenser, removing and installing

Version "1" (with bolted connection and bracket), removing

Version "2" (with block and bolt connection), removing

Version "3" (with two block connections), removing

Installing (all models)

Disconnecting

Connecting

Refrigerant lines on compressor, disconnecting and connecting (compressor with A/C compressor regulator valve -N280-)

Removing (compressor drive via belt)

A/C system, running after installation of compressor

Refrigerant lines for condenser, removing and installing

Removing refrigerant lines on version "1" (two connectors)

Removing refrigerant lines on version "2" (two block connections on left side)

Removing refrigerant lines on version "3" (one block connection on left side and one on right side)

Removing, versions "1" and "2"

Removing, version "3"

Capacities

Condenser version

Air conditioner unit

Refrigerant oil

Compressor bracket, removing and installing (6 cyl. engine, compressor with A/C clutch -N25-)

Complete air conditioner unit, removing and installing

A/C unit, disassembling and assembling

Air distribution housing, disassembling and assembling

Air duct with intake housing, disassembling and assembling

Air duct and intake housing (vehicles up to model year 2001)

Air duct and intake housing (vehicles from model year 2002)

A/C does not cool (cooling has stopped completely)

Insufficient cooling during all driving or engine speed (RPM)

A/C compressor noisy

A/C compressor noisy immediately after switching A/C ON and/or when driving around corners or braking "refrigerant shock" - refrigerant system overcharged

With an otherwise properly operating A/C system, water sprays out of instrument panel vents

A/C system, replacing components

For leaking or damaged components (except for compressor and accumulator), A/C system was completely empty (no charge)

For leaky or damaged components (except for the compressor and accumulator) there is still refrigerant in the A/C system

Replace compressor, without it being necessary to blow through the refrigerant system with compressed air and nitrogen (e.g. exterior damage after an accident)

Replace compressor due to leaks or interior damage (e.g. noises or no power)

Replace accumulator and restrictor after blowing through the A/C system e.g. caused by penetrating moisture (the A/C system was open over a long period of time) or contamination (d

Replace accumulator, without it being necessary to blow through A/C system with compressed air and nitrogen (e.g. damage caused by an accident), no refrigerant flowed out and no mo

All sections

Discharging Audi A6 C5

Air Conditioning 1 illustration ~131 words

Discharging

Make sure initial set-up has been performed on recovery/recycling/recharging unit before discharging A/C system.

Connect red high pressure hose -A- of refrigerant recovery/recycling/recharging unit to high pressure service valve (fitting) on vehicle and open coupler valve.
Leave blue low pressure hose -B- of refrigerant recovery/recycling/recharging unit disconnected.

Scheme 91

Scheme 91

Scheme 91

Note. Only the high pressure service valve is used for A/C system servicing. Perform all A/C system service operations (i.e. discharging, evacuating and charging) through the high pressure service valve only.

CAUTION

Always follow manufacturer's instructions when using a refrigerant/recovery/recycling/recharging unit.

Following refrigerant recovery/recycling/recharging unit manufacturer's instructions, discharge A/C system into refrigerant recovery/recycling/recharging unit. See «A/C REFRIGERANT SYSTEM (R-134A), DISCHARGING»(/audi/a6/c5-1997-2001/remont/automatic-hvac-system/#air-conditioning__ac-refrigerant-system-r-134a-discharging) .
After emptying A/C system, disconnect power supply from A/C clutch -N25- (e.g. disconnect harness connector from A/C pressure switch -F129-) to prevent accidental compressor operation with A/C system discharged.