6
2. Precaution for Using R32 Refrigerant
Pay careful attention to the following precaution points and the installation work procedures:
WARNING
1.
The appliance shall be stored, installed and operated in a well ventilated room with indoor floor area larger than A
min
(m
2
) [refer
Table A] and without any continuously operating ignition source.
Keep away from open flames, any operating gas appliances or any operating electric heater. Else, it may explode and cause
injury or death.
2.
When connecting flare at indoor side, make sure that the flare connection is used only once, if torqued up and released, the
flare must be remade.
Once the flare connection was torqued up correctly and leak test was made, thoroughly clean and dry the surface to remove oil,
dirt and grease by following instructions of silicone sealant. Apply neutral cure (Alkoxy type) & ammonia-free silicone sealant
that is noncorrosive to copper & brass to the external of the flared connection to prevent the ingress of moisture on both the gas
& liquid sides.
(Moisture may cause freezing and premature failure of the connection)
3.
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).]
4.
Ensure that foreign matter (oil, water, etc.) does not enter the piping.
Also, when storing the piping, securely seal the opening by pinching, taping, etc. (Handling of R32 is similar to R410A.)
5.
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.
6.
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.
7.
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.
8.
A logbook shall be maintained. The results of these checks shall be recorded in the logbook.
9.
In case of ventilations in occupied spaces shall be checked to confirm no obstruction.
10.
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.
11.
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.
12.
Air-conditioner piping in the occupied space shall be installed in such a way to protect against accidental damage in operation
and service.
13. Precautions shall be taken to avoid excessive vibration or pulsation to refrigerating piping.
14.
Ensure protection devices, refrigerating piping and fittings are well protected against adverse environmental effects (such as the
danger of water collecting and freezing in relief pipes or the accumulation of dirt and debris).
15.
Expansion and contraction of long runs piping in refrigerating systems shall be designed and installed securely (mounted and
guarded) to minimize the likelihood hydraulic shock damaging the system.
16. Protect the refrigerating system from accidental rupture due to moving furniture or reconstruction activities.
17.
To ensure no leaking, field-made refrigerant joints indoors 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 4.15MPa). No leak shall be detected.
