62A-1
AIR CONDITIONING
Air conditioning: Precautions for the repair
AIR CONDITIONING or CLIMATE CONTROL
62A
I - SAFETY
Refrigerant is heavier than air. As a result there is a risk
of asphyxia for those working close to the ground and
less than 5 m away from the working area (pit, well, air
vents, etc.).
Switch on gas extraction systems.
At temperatures above 100˚C, the refrigerant will de-
compose and produce a highly irritant gas.
II - GENERAL RECOMMENDATIONS
It is possible to place components in the drying oven
after painting or to carry out work near the system if the
temperature does not exceed 80˚C.It is essential to follow the routing of the connecting
pipes.
Ensure that the refrigerant connecting pipes are cor-
rectly fitted so that they will not come into contact with
metal parts in the engine compartment. IMPORTANT
The following must be worn when handling refrige-
rant:
-gloves,
-protective goggles (with side shields if possible).
In the event of refrigerant fluid coming into contact
with the eyes, rinse well with clean water continu-
ously for 15 minutes. If possible, have an eye rinse
unit available.
If refr igerant comes into contact with your eyes,
consult a doctor immediately. Inform the doctor that
the burns were caused by R134A refrigerant.
In the event of contact with other unprotected parts
of the body (event though the safety advice has
been observed), r inse well with clean water continu-
ously for 15 minutes.
IMPORTANT
Work requiring the use of refrigerant must be car-
ried out in a well-ventilated area.
The refrigerant must not be stored in a shaft, a pit,
a hermetically sealed room, etc.
Refrigerants are colourless and odourless fluids.
IMPORTANT
It is forbidden to smoke close to an open refrigerant
circuit.
IMPORTANT
To prevent refrigerant from leaking, never repair a
faulty air conditioning circuit component.
Replace all faulty components.
WARNING
In order to avoid any refrigerant leaks, do not dam-
age (deform, twist, etc.) the pipe.
WARNING
To avoid damaging the surface of the air condition-
ing pipes when removing the seals, do not use a
tool with a metallic end piece.
WARNING
To prevent moisture from entering the system,
place plugs on the cold loop components which are
open to the air.
WARNING
To prevent any leaks, check that the seal and sur-
face of the pipe are in good condition. The seal and
the surface must be clean and free from scratches.
WARNING
Lubricants are not mutually compatible: always
observe the type and quantity of oil recommended
for each compressor even when topping up as this
could damage the cold loop components.
Always close the oil cans again after use to keep
moisture out and never use oil contained in a can
that has been open for a long time (viscous appear-
ance).
62A-9
AIR CONDITIONING
Refrigerant circuit: Draining - Filling
AIR CONDITIONING or CLIMATE CONTROL
62A
I - RECOVERING REFRIGERANT FLUID
a
When draining or checking the refrigerant fill load,
three scenarios are to be taken into account:
-the engine is running and the air conditioning is in
operation (A),
-the engine is running but the air conditioning is not
in operation (B),
-the engine is not running nor is the air conditioning
in operation (C).
aScenario A:
-Operate the air conditioning until the cooling fan
assembly is triggered twice,
-Switch off the engine,
-drain for the first time (note down the original val-
ue),
-wait 15 minutes,
-check that the relative pressure is no more than 0
bar,
-repeat the cycles until the relative pressure is equal
to or less than 0 bar,
-add together the values of the various draining op-
erations; the fill is confirmed as being correct if the
volume of refrigerant fluid is the specified fill +35g
or -100g.
Scenario B:
-run the engine until the cooling fan is triggered
twice,
-Switch off the engine,-drain for the first time (note down the value),
-wait 15 minutes,
-run the engine until the cooling fan is triggered
twice,
-Switch off the engine,
-drain for the second time (note down the value),
-repeat the cycles until the relative pressure is equal
to or less than 0 bar,
-add together the values of the various draining op-
erations; the fill is confirmed as being correct if the
volume of refrigerant fluid is the specified fill +35g
or -100g.
Scenario C:
-drain for the first time (note down the value),
-wait 2 hours,
-repeat the cycles until the relative pressure is equal
to or less than 0 bar,
-add together the values of the various draining op-
erations; the fill is confirmed as being correct if the
volume of refrigerant fluid is the specified fill +35g
or -100g.
II - CREATING A VACUUM
aIt is essential to carry out vacuum extraction correct-
ly before loading, otherwise the air conditioning will
not work properly.
There are two scenarios to consider:
-vacuum created immediately after discharge (sce-
nario A),
-vacuum created after an interval of several hours
or days (scenario B).
Scenario A:
-creation of a vacuum takes 20 minutes.
Scenario B:
-creation of a vacuum takes 45 minutes to elimi-
nate any trace of moisture.
aTest the seal once the vacuum has been created
(some stations do this automatically).
III - FILLING
aFill up the refrigerant circuit using the refrigerant
charging station. Note:
-If the air conditioning circuit is fitted with a sin-
gle filler valve, some filling equipment only
requires the use of the high pressure pipe (refer
to the filling station instructions).
-Depending on the situation, run the system for
a few minutes before recovering the coolant to
improve drainage.
Note:
It is essential to follow these procedures to pre-
vent:
- gas escaping when the circuit is opened,
- pollution of the environment through the release
of gas into the atmosphere when the circuit is
opened or when a vacuum is created.
