Special tools:
Tool Name
Requirement(s) for Use
Mini
Vacuum
Pump
It should be an explosion-proof vacuum pump; can ensure certain precision
and its vacuum degree should be lower than 10Pa.
Filling Device
It should be a special explosion-proof filling device; have certain precision and
its filling deviation should be less than 5g.
Leak Detector
It should be calibrated regularly; and its annual leak rate should not exceed
10g.
Concentration
Detector
A) The maintenance site should be equipped with a fixed-type combustible
refrigerant concentration detector and connected to a safeguard alarm
system; its error must be not more than 5%.
B) The installation site should be equipped with a portable combustible
refrigerant concentration detector which can realize two-level audible and
visual alarm; its error must be not more than 10%.
C) The concentration detectors should be calibrated regularly.
D) It is necessary to check and confirm the functions before using the
concentration detectors.
Pressure Gauge
A) The pressure gauges should be calibrated regularly.
B) The pressure gauge used for Refrigerant 22 can be used for Refrigerants
R290 and R161; the pressure gauge used for R410A can be used for
Refrigerant 32.
Fire Extinguisher
It is necessary to carry fire extinguisher(s) when installing and maintaining an
air conditioner. On the maintenance site, there should be two or more kinds of
dry powder, carbon dioxide and foam fire extinguishers and that such fire
extinguishers should be placed at stipulated positions, with eye-catching
labels and in handy places.
Maintenance
1. Inspections before maintenance.
1) Inspection of maintenance environment
There should be no leaked refrigerant in the room before operation.
It is only allowed to operate in a room which meets the area requirement on the nameplate.
It is necessary to make the room keep a continuous ventilation state at the time of maintenance.
The room in the maintenance should be free from fire or welding, smoking, drying oven or any
other goods temperature higher than 370
℃
(R290)/548
℃
(R32) which easily produces fire.
During the maintenance, it is necessary to ensure that any person’s any mobile phone or any
electronic product with radiation in the room is powered off.
The maintenance area should be equipped with a drying powder or carbon dioxide fire
extinguisher and that such fire extinguisher can work.
2) Inspection of maintenance equipment
Check the maintenance equipment is applicable to the refrigerant or not and it is only allowed to
use the professional equipment recommended by the air conditioner manufacturer.
Check the refrigerant leak detector whether has been calibrated. The set maximum alarm
concentration of the refrigerant leak detector should not exceed 25% of the lower explosion limit
(LEL), the refrigerant leak detector must be working during maintenance.
3) Inspection of air conditioner
It is necessary to ensure that the air conditioner is in reliable ground connection before
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