Check compressor cutout and conduct remedial action

AR83.30-T-1738AB

Check compressor cutout and conduct remedial action

12.06.2019

Model

NMB671.030

with code HKC (Sütrak AC 353 air conditioning without roof heater)

1

Pressure-side testing and filling valve

2

Pressure gage

3

Suction side testing and filling valve

4

Protective cap

5

Filter dryer manual shutoff valve

6

Condenser fan electrical connector

7

Clutch hub



Remove

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

 Danger

Risk of explosion caused by welding or soldering work on closed air conditioning system. Risk of poisoning caused by inhaling overheated refrigerant vapors. Risk of injury to skin and eyes caused by contact with liquid refrigerant.

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 areas. Carry out repair work on the air conditioning system circuit only after the system has been drained.

AS83.00-Z-0001-01A

 Danger

Risk of death caused by falling from vehicle roof. Risk of injury to other persons caused by falling objects during work in roof area.

AS65.00-Z-0002-01A

Topical note

Protect air conditioning circuit and components from moisture when carrying out repair work

AH83.30-N-0005-01A

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

1

Unscrew plugs over pressure side test and filling valve (1) and intake side test and filling valve (3)

2

Connect air conditioning vacuum and recycling unit to pressure side test and filling valve (1) and to intake side test and filling valve (3)

 Observe operating instructions for air conditioning vacuum and recycling unit.

3

Remove paneling of condenser unit

AR83.50-T-5000AB

4

Open left trim of evaporator unit

AR83.50-T-5010AB

 Only perform operation steps for opening.

5

Start engine

6

Switch on air conditioning

 See air conditioning system operating instructions

Check high-pressure switch

7

Disconnect fan electrical connector (6) with aid of helper

8

Observe pressure display on manometer (2)


If the high-pressure switch shutoff pressure is exceeded and the coupling hub (7) still rotates, immediately switch off air conditioning system and engine
to prevent damage to the air conditioning system.

 If high-pressure switch shutoff pressure is exceeded and the coupling hub (7) rotates,

the high-pressure switch must be replaced:



Remove/install the air conditioning's high-pressure switch (roof equipment)
Model NMB671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)
except code HKA (Konvekta ACX 602 air conditioning with roof heater)

AR83.50-T-5070AB

High-pressure switch shutoff pressure

*BE83.30-N-1001-03C

9

Connect fan electrical connector (6)

10

Observe pressure display on manometer (2)

 If high-pressure switch cut-in pressure is undershot and the coupling hub (7) does not rotate,

the high-pressure switch must be replaced:



Remove/install the air conditioning's high-pressure switch (roof equipment)
Model NMB671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)
except code HKA (Konvekta ACX 602 air conditioning with roof heater)

AR83.50-T-5070AB

High-pressure switch cut-in pressure

*BE83.30-N-1002-03C

Check low-pressure switch

11

Unscrew cover cap (4)

12

Slowly close filter dryer manual shutoff valve (5) until the low-pressure switch shutoff pressure is reached on the manometer (2)


Do not completely close filter dryer manual shutoff valve (5)
to prevent damage to the air conditioning system.

 If the low-pressure switch shutoff pressure is undershot and the coupling hub (7) rotates,

the low-pressure switch must be replaced:



Remove/install the air conditioning's low pressure switch (roof equipment)
Model NMB671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)
except code HKA (Konvekta ACX 602 air conditioning with roof heater)

AR83.50-T-5140AB

Low-pressure switch shutoff pressure

*BE83.30-N-1003-03C

13

Slowly open filter dryer manual shutoff valve (5) until the low-pressure switch cut-in pressure is reached on the manometer (2)

 If the low-pressure switch cut-in pressure is exceeded and the coupling hub (7) does not turn,

the low-pressure switch must be replaced:



Remove/install the air conditioning's low pressure switch (roof equipment)
Model NMB671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)
except code HKA (Konvekta ACX 602 air conditioning with roof heater)

AR83.50-T-5140AB

Low-pressure switch cut-in pressure

*BE83.30-N-1004-03C



Install

14

Switch off the air conditioning

15

Turn off engine

16

Open filter dryer manual shutoff valve (5) fully

17

Screw on cover cap (4)

18

Close left trim of evaporator unit

AR83.50-T-5010AB

19

Install condenser unit paneling

AR83.50-T-5000AB

20

Remove air conditioning vacuum and recycling unit

21

Screw on plugs over pressure side test and filling valve (1) and intake side test and filling valve (3)

Check values for air conditioning pressure switch

Number

Designation

Model 671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)

BE83.30-N-1001-03C

High-pressure switch shutoff pressure

bar

23,5 (0,4)

Check values for air conditioning pressure switch

Number

Designation

Model 671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)

BE83.30-N-1002-03C

High-pressure switch cut-in pressure

bar

16,6 (1,0)

Check values for air conditioning pressure switch

Number

Designation

Model 671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)

BE83.30-N-1003-03C

Low-pressure switch shutoff pressure

bar

0,35 (0,1)

Check values for air conditioning pressure switch

Number

Designation

Model 671.030
with code HKC (Sütrak AC 353 air conditioning without roof heater)

BE83.30-N-1004-03C

Low-pressure switch cut-in pressure

bar

2,2 (0,3)