Performing short check on air conditioning

AR83.30-L-1209A

Performing short check on air conditioning

24.2.00



Inspecting

Danger!

Risk of explosion from welding or braizing work on closed air conditioning system. Risk of poisoning from inhaling overheated refrigerant vapors. Risk of injury from skin and eye contact with liquid refrigerant.

Do not carry out any welding work on the closed air conditioning system or in the surrounding area. No smoking or naked flames. Wear eye protection and protective gloves. Work only in well ventilated areas. Do not carry out repair work on the circuit of the air conditioning system unless the system is drained.

AS83.00-Z-0001-01A

Danger!

Risk of accident from vehicle starting off by itself when engine running. Risk of injury from bruises and burns if you place your hand into the engine when it is started or when it is running.

Secure vehicle to prevent it moving off by itself.
Wear closed and close-fitting work clothes.
Do not grasp hot or rotating parts.

AS00.00-Z-0005-01A

1

Make the required preparations for testing the air conditioning system on the vehicle

 in order to make the testing preparations,
park vehicle in a cool place and keep vehicle interior open.

Set heater control valve to "cold".

Set heating and ventilation system to fresh air mode.

Side nozzles, center nozzles and footwell flaps must be fully open.

2

Attach suction, treatment and filling device to testing and filling valves (1, 2)

 Observe suction, treatment and filling device operating instructions.



*WE58.40-Z-1002-22A

3

Start vehicle engine and allow to run at idle speed

4

Switch air conditioning on

 The idling speed of the engine must increase when the air conditioning is switched on.

No idling speed increase: 

Check engine speed sensor operation. If a problem is found: 

Replace engine speed sensor

5

Set blower rotary switch to maximum blower setting

6

Read off pressure from high-pressure manometer when switching off the refrigerant compressor

 Compare pressure indicated on high-pressure manometer to specified upper switch-off pressure value: 

*BE83.30-N-1001-03B

If pressure drops below lower switch-off pressure limit, refrigerant compressor must not switch itself on, and must switch itself off if it is operating at the time.

*BE83.30-N-1002-03B

If upper switch-off pressure is not reached: 

Check air conditioning circuit for leaks using air conditioning system leak detector (5) and remedy cause of leaks.

AR83.30-D-1209-01A

Evacuate air conditioning system, leak test

AR83.30-L-1762A

Fill air conditioning system, replenish (gaseous)

AR83.30-L-1767A

Fill air conditioning system (liquid)

AR83.30-L-1777A

If upper switch-off pressure is exceeded: 

Remove pressure switch from fluid reservoir (4)

AR83.30-L-5620A

7

Insert temperature measuring device (1) probe into center nozzle air outlet and check outlet air temperature

 Move blower rotary switch to level "1" and check air outlet temperature after approx. 5 mins. After this time the refrigerant compressor must switch on and off occasionally.

If the switch-off temperature deviates when the refrigerant compressor switches off: 

*BE83.30-N-1001-04B

Check evaporator temperature switch.

If the lower temperature limit or

*BE83.30-N-1002-04B

upper temperature limit of the air outlet is not reached: 

*BE83.30-N-1003-04B

Check refrigerant compressor on/off switching mechanism or check refrigerant pressure before and after the refrigerant compressor.

If refrigerant compressor does not switch on:  Check fuse in fuse box, replace if necessary and remedy cause. Possible cause may be engine overheating.



*WH58.30-Z-1005-08A

8

Switch air conditioning off and turn engine off

9

Switch off suction, treatment and filling device



*WE58.40-Z-1002-22A

10

Remove suction and pressure lines from testing and filling valves (1, 2)

Number

Designation

Models 667, 668, 670
with code H03

BE83.30-N-1001-03B

Upper switch-off pressure switch

bar

26 (2.6)

BE83.30-N-1002-03B

Lower switch-off pressure switch

bar

2 (0.2)

Number

Designation

Models 667, 668, 670
with code H03

BE83.30-N-1001-04B

Lower refrigerant compressor switch-off temperature

°C

1

BE83.30-N-1002-04B

Air outlet lower temperature limit
(after refrigerant compressor has been on for 5 min.)

°C

5

BE83.30-N-1003-04B

Air outlet upper temperature limit
(after refrigerant compressor has been on for 5 min.)

°C

14

Number

Designation

WH58.30-Z-1005-08A

Temperature measuring device

WE58.40-Z-1002-22A

Air conditioning service station