Check air conditioning system for leakage

AR83.30-S-1761E

Check air conditioning system for leakage

18.12.2019

Model

447

with code HH4 (THERMOTRONIC automatic climate control)

Model

447

with code HH9 (Air conditioner, automatic heater control)

Model

447

with code HZ7 (TEMPMATIC semi-automatic air conditioning in rear)

Model

448

Modification notes

16.12.2019

Basic data reference, added

Operation step 2

 Danger

Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)

Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.Typ 447 mit Motor 780

AS00.00-Z-0035-01A

 Danger

Risk of explosion when using a forming gas with incorrect mixing ratio. Risk of suffocation due to inhalation of forming gas. Risk of injury due to bursting of high-pressure hoses.

Wear safety glasses and protective gloves. No smoking or open flames. Work in well-ventilated rooms only.

AS83.00-Z-0001-02A

 Danger

Risk of fire due to ignition of R1234yf refrigerant on hot components. Risk of poisoning caused by inhaling overheated refrigerant vapors. Risk of injury to skin and eyes caused by contact with escaped R1234yf refrigerant and when working on pressurized parts. Risk of explosion due to formation of ignitable refrigerant/air mixtures

Never perform welding work on or near a closed air conditioning system. No smoking or open flames. Wear safety glasses and protective gloves. Work only in well ventilated rooms. Carry out repair work on the air conditioning system circuit only after the system has been evacuated.

AS83.00-Z-0007-01A

 Warning

Risk of poisoning caused by inhaling overheated refrigerant vapors from an air conditioning system containing R134a. Risk of injury to skin and eyes caused by contact with liquid R134a refrigerant and when working on pressurized parts

Never perform welding work on or near a closed air conditioning system. No smoking or open flames. Wear safety glasses and protective gloves. Work only in well ventilated rooms. Carry out repair work on the air conditioning system circuit only after the system has been evacuated.

AS83.00-Z-0006-01A

Topical note

General information on vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system as well as personal protective equipment

Typ 447 mit Motor 780

AH00.00-Z-0300-01A

Topical note

Procedure for a damaged or leaky air conditioning system

AH83.30-N-0004-01A

Notes on handling refrigerant R134a

AH83.30-N-0003-01A

Notes on handling refrigerant R1234yf

AH83.30-P-0003-02A



Check

1

Evacuate air conditioning system.

Model 447 except code HX1 (Refrigerant R-1234yf), Model 448

AR83.30-S-1760E

Model 447 with code HX1 (R-1234yf refrigerant)

AR83.30-S-1760EF

2

Fill refrigerant circuit with forming gas and check for pressure drop.



000 588 19 21 00 Leak tester

WS83.00-P-0035B


Temperature changes during the pressure test (e.g. through change in weather or cooling) can cause pressure surges.
Consistent ambient conditions must therefore be strictly ensured.
Otherwise, the check values will be changed.

 Observe operating instructions for leak tester.

 Fill refrigerant circuit with forming gas only when the engine is cold or when the axle drive module is cold.

Model 447 with engine 780Pressure drop in refrigerant circuit filled with test gas

*BE08.50-N-1001-02F

Model 447 with engine 274, 622, 651, 654, model 448Pressure drop in refrigerant circuit filled with test gas

*BE83.30-N-1001-04E

3

Determine leakage in refrigerant circuit using gas detection unit.

If no pressure drop was detected.



000 588 03 21 00 Gas detector

WS47.00-P-0019B

 Observe operating instructions for gas detection unit.

If leaks are found,



Replace affected component parts of refrigerant circuit.

4

Vent forming gas from refrigerant circuit on leak tester.

5

Fill air conditioning.

Model 447 except code HX1 (Refrigerant R-1234yf), Model 448

AR83.30-S-1760E

Model 447 with code HX1 (R-1234yf refrigerant)

AR83.30-S-1760EF

Refrigerant circuit of cooling system

Number

Designation

Engine 780.701/702 in model 447

BE08.50-N-1001-02F

Pressure drop in refrigerant circuit filled with test gas

Test pressure

bar

15

Test period

h

2

Permissible ambient temperature fluctuation

°C

2

Pressure drop

bar

0

Air conditioning

Number

Designation

Model 447, 448

BE83.30-N-1001-04E

Pressure drop in refrigerant circuit filled with test gas

Test pressure

bar

15

Test period

h

2

Permissible ambient temperature fluctuation

°C

2

Pressure drop

bar

0