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1 689 975 257
2019-05-15
|
Robert Bosch GmbH
14 | ACS 652 | Service phases
en
8.3
Vacuum phase and recycling
(simultaneous)
8.3.1
Vacuum phase
i
During vacuum generation in the vehicle air condi-
tioning system, the refrigerant is prepared in the
internal refrigerant cylinder to remove the non-con-
densing gases before filling and to filter the refriger-
ant.
1.
The ACS 652 is connected to the vehicle with the
service hoses T1 and T2.
2.
Open the service quick-release coupling valves.
The pressure on the high and low pressure side of
the vehicle air conditioning system is indicated on
the pressure gages M1 and M2.
i
By selecting the LOW and HIGH ports (through the
software) EVHP1, EVHP2, EVLP1, EVLP2, EV10 so-
lenoid valves are opened and the A/C system starts
communication with P1 pressure transducer. P1
checks the pressure in the vehicle air conditioning
system (refrigerant present in the vehicle air condi-
tioning system or not).
i
If the pressure in the vehicle air conditioning system
is below the set value, the vehicle air conditioning
system is empty and the ACS 652 starts vacuum
generation.
i
If the pressure is above the set value, there is still re-
frigerant in the vehicle air conditioning system, and
it must be extracted before vacuum generation.
3.
Press the
<
Vacuum
> key.
EV1 and EV10 are opened and the vacuum pump
(2) starts.
i
The vacuum pump generates a maximum vacuum of
0.05 mbar. This depends on the duration of vacuum
generation.
i
The refrigerant in the internal refrigerant cylinder is
fed through the internal refrigerant circuit and pre-
pared in each vacuum phase.
8.3.2
Recycle
i
During the vacuum function, the refrigerant recycle
starts automatically to further improve its purity
before the recharge.
i
Some seconds after the vacuum stage has started,
the ecu excites the EV5 and EV6 solenoid valves by
opening them and starting compressor 6.
i
In that way, refrigerant is sucked from storage bottle
7 and is conveyed through the filter F1, the expan-
sion valve 3, the still/separator 4 until reaching the
tank again, as it happens in the recovery stage.
i
This function favours the automatic discharge of non
condensable gases inside the storage bottle.