Peugeot 308: Checking for leaks : Air conditioning circuit

ESSENTIAL : Observe the safety and cleanliness recommendations .

ESSENTIAL : All personnel carrying out work on a vehicle fitted with traction batteries must have received specific electric vehicle training and be authorised to work on these vehicles(observe the regulations in force in the respective country).

ESSENTIAL : All personnel working on vehicles with a fuel cell stack must have completed the STELLANTIS training courses required to work on these vehicles(observe the regulations in force in the respective country).

1. Workshop equipment

List of the different equipment which can be used to carry out the sealing check :

• Electronic leak detector
• Nitrogen leak detection kit ; Leak detector(aerosol)
• Filling station with injection of tracer and ultraviolet lamp

2. Preliminary operations

Read the residual pressure in the air conditioning circuit ; Using the filling station :

• If the residual pressure is higher than zero : Search for the leak ; Using an electronic leak detector
• If the residual pressure is zero : Search for the leak ; Using the nitrogen leak detection kit

3. Searching for a leak; using an electronic leak detector

3.1. Procedure

CAUTION : To search for a leak, using the electronic leak detector, the air conditioning circuit must not be empty.

N.B. : An initial check can be carried out; using a "bubbling" product (which, when sprayed onto the circuit, forms bubbles where there is a leak).

Carry out an initial leak search, with the air conditioning off, then a second with the engine running and the air conditioning compressor operating.

N.B. : As the refrigerant gas is heavier than air, position the electronic leak detector sensor below the air conditioning circuit during the leak search.

Place the electronic leak detector near the different parts of the air conditioning circuit.

Position the electronic leak detector sensor below the unions or crimps.

Ventilate using bellows the area in which the electronic leak detector has identified a leak and repeat the check.

N.B. : If the leak is not detected in this way, use the following method.

3.2. Special feature : Leak from the air conditioning evaporator

If the electrical leak detector does not detect any leaks during the check, the leak can be located at the air conditioning evaporator : Apply the following method :

• Place the blower control on minimum
• Bring the electrical leak detector towards the air vent to check for a leak

If the electrical leak detector detects a leak during the check : Apply the following method :

• Place the air blower control in the maximum position (for ventilation)
• Repeat the check to confirm the detection of the leak at the air conditioning evaporator

4. Searching for a leak; using the nitrogen leak detection kit or using trans-diazene N2H2

CAUTION : To search for a leak, using the nitrogen leak detection kit, the air conditioning circuit must be empty and the residual pressure in the circuit zero.

N.B. : Nitrogen is not a pollutant gas.

Install the nitrogen leak detection kit equipped with an adjustable pressure reducing valve.

Set the pressure to 5 bars for an initial sealing check.

Set the pressure to 15 bars maximum for a second sealing check.

Couple the nitrogen bottle pressure reducing valve pipe to an air conditioning circuit union.

Close the tap on the nitrogen bottle.

Check whether the pressure on the pressure gauge drops.

Search for major leaks by locating the noise.

To check the sealing of the air conditioning circuit, spray a nitrogen leak detector or a hydrogen-based leak detector if using trans-diazene "N2H2".

N.B. : If the leak is not detected in this way, use the following method.

5. Searching for leaks by injecting tracer

ESSENTIAL : Use an ultraviolet lamp and a pair of yellow goggles.

CAUTION : It is compulsory to affix a sticker indicating the presence of tracer in the engine compartment.

To detect a leak on the air conditioning circuit, fill to a level equivalent to half the nominal filling and inject a dose of tracer (Inject approximately 7,5 ml of tracer ).

Switch on the air conditioning to favour the distribution of the tracer in the air conditioning circuit.

Light the different parts of the air conditioning circuit to identify a fluorescent stain at the leak; using the ultraviolet lamp.

N.B. : In the air conditioning circuit, the tracer is conveyed by the refrigerant . A fairly long period of driving with the air conditioning in operation may be necessary to allow the tracer diluted in the refrigerant to leave a external mark at the leak.

CAUTION : Recover all of the refrigerant contained in the air conditioning circuit once the leak has been detected.