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2. Precaution for Using R32 Refrigerant
The basic installation work procedures are the same as conventional refrigerant (R410A, R22) models.
However, pay careful attention to the following points:
WARNING
1.
Since the working pressure is higher than that of refrigerant R22 models, some of the piping and installation and service tools are
special.
Especially, when replacing a refrigerant R22 model with a new refrigerant R32 model, always replace the conventional piping with the
R32 and R410A piping on the outdoor unit side.
For R32 and R410A, the same pipe can be used.
2.
The mixing of different refrigerants within a system is prohibited. Models that use refrigerant R32 and R410A have a different charging
port thread diameter to prevent erroneous charging with refrigerant R22 and for safety.
Therefore, check beforehand. [The charging port thread diameter for R32 and R410A is 12.7 mm (1/2 inch).]
3. Ensure that foreign matter (oil, water, etc.) does not enter the piping.
4.
Operation, maintenance, repairing and refrigerant recovery should be carried out by trained and certified personnel in the use of
flammable refrigerants and as recommended by the manufacturer. Any personnel conducting an operation, servicing or maintenance
on a system or associated parts of the equipment should be trained and certified.
5.
Any part of refrigerating circuit (evaporators, air coolers, AHU, condensers or liquid receivers) or piping should not be located in the
proximity of heat sources, open flames, operating gas appliance or an operating electric heater.
6.
The user/owner or their authorized representative shall regularly check the alarms, mechanical ventilation and detectors, at least once
a year, where as required by national regulations, to ensure their correct functioning.
7. A logbook shall be maintained. The results of these checks shall be recorded in the logbook.
8. In case of ventilations in occupied spaces shall be checked to confirm no obstruction.
9.
Before a new refrigerating system is put into service, the person responsible for placing the system in operation should ensure that
trained and certified operating personnel are instructed on the basis of the instruction manual about the construction, supervision,
operation and maintenance of the refrigerating system, as well as the safety measures to be observed, and the properties and
handling of the refrigerant used.
10.
The general requirement of trained and certified personnel are indicated as below:
a) Knowledge of legislation, regulations and standards relating to flammable refrigerants; and,
b) Detailed knowledge of and skills in handling flammable refrigerants, personal protective equipment, refrigerant leakage prevention,
handling of cylinders, charging, leak detection, recovery and disposal; and,
c) Able to understand and to apply in practice the requirements in the national legislation, regulations and Standards; and,
d) Continuously undergo regular and further training to maintain this expertise.
11. Protect the refrigerating system from accidental rupture due to moving furniture or reconstruction activities.
12.
To ensure no leaking, refrigerant joints shall be tightness tested. The test method shall have a sensitivity of 5 grams per year of
refrigerant or better under a pressure of at least 0,25 times the maximum allowable pressure (>1.04MPa, max 4.3MPa). No leak shall
be detected.
