01.07.2022
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AHP60-14/18 -
Installation, Use and Maintenance
Measure
Performed
Remark
12
■ The refrigerant detector must be suitable for the R32
refrigerant to be detected.
■ The refrigerant detector must not contain any potential
source of ignition.
■ Calibrate the refrigerant detector to suit the refrigerant used.
Set the response threshold to < 3 g/a, suitable for propane.
Leak detection using leak detection liquids:
■ Leak detector liquids associated with most refrigerants are
suitable.
Warning
Liquid leak detectors containing chlorine react with the
refrigerant, causing corrosion.
■ Do not use liquid leak detectors containing chlorine.
Measures to be taken when there is a leak in the
refrigeration circuit:
■ Immediately extinguish any open flame in the vicinity of the
heat pump.
■ Always recover all refrigerant from the refrigeration circuit if
brazing work is required to eliminate the leak.
Flush the area to be brazed with oxygen-free nitrogen before
and during brazing.
13
Recover the refrigerant
Recovering and evacuation of the refrigerant
If any work is to be done in the refrigerant circuit for repair
or other reasons, it should be done according to standard
procedures. In general, special care must be taken with regard
to the flammability of the refrigerant. The following procedure
should be followed in all cases:
- recover the refrigerant;
- purge the refrigerant circuit with dry nitrogen; evacuate;
- purge again with inert gas;
- open up the refrigerant circuit by cutting or brazing it.
The refrigerant charge must be recovered in an appropriate
recycling bottle. The refrigerant circuit must be purged with
nitrogen to ensure safety. This process must be repeated
several times if necessary. Under no circumstances should
compressed air or oxygen be used.
The purging process must be carried out by bringing oxygen-
free nitrogen into the vacuum and raising the pressure to the
operating pressure level.
Then the excess pressure must be lowered and evacuated.
This process must be repeated until no refrigerant remains in
the system. Once the last purging process is completed, the
pressure in the system must be reduced to the atmospheric
pressure level. This is particularly important if brazing is to be
carried out on the refrigerant circuit.
Ensure that the outlet of the vacuum pump leads to a well
ventilated area and that there are no flammable sources in
the vicinity.
