LCX
RG66010687_rev.00
35
Do not use oxygen in the place of nitrogen as a test agent, since this could cause a risk
of explosion as well as the certainty of extensive oxidisation in high-temperature areas.
10.5 HARD VACUUM AND DRYING OF THE COOLING CIRCUIT
To achieve a hard vacuum in the cooling circuit it is necessary to use a pump capable of generating a
high degree of vacuum, i.e. 15 Pa of absolute pressure.
If there is no suitable vacuum pump available, or whenever the circuit has remained open for long periods
of time, you are strongly recommended to adopt the triple evacuation method. This method is also
recommended when there is a presence of humidity within the circuit.
The vacuum pump should be connected to the inlets.
The procedure to be carried out is as follows:
- Evacuate the circuit until you reach an absolute pressure of at least 35 Pa. At this point inject nitrogen
into the circuit until you reach a relative pressure of about 1 bar.
- Repeat the step described above.
- Carry out the step described above for the third time, but in this case attempting to reach the hardest
vacuum possible.
Using this procedure you can easily remove up to 99% of pollutants.
10.6 CHARGING WITH R410A REFRIGERANT
- Connect the tank of refrigerant gas to the male 1/4 SAE inlet situated on the liquid line after discharging
a little gas to eliminate air in the connection pipe.
-
Carry out the charging operation with the refrigerant in liquid form
until you reach 75% of the total
charge.
- Then connect to the inlet on the intake line and complete the charging process with the refrigerant
in
liquid form
until no more bubbles can be seen on the liquid level indicator and the operating
parameters specified in the section "Checking the refrigerant level" have been reached.
Since R410A is a binary blend of R32 and R125, it is advisable to charge with refrigerant
in the liquid phase to ensure the correct percentage of the 2 components.
Charge through the charging inlet provided between the expansion valve and evaporator
inlet.
A unit that was originally charged with R410A in the factory cannot be charged with other
refrigerants.
