Aiwa -09CHSRINV/TP11 Service Manual page 27

of the refrigerant leak detector should not exceed 25% of the lower explosion limit (LEL), the refrigerant
leak detector must be working during maintenance.
2) Inspection of air conditioner
 It is necessary to ensure that the air conditioner is in reliable ground connection before maintenance.
 Make sure powered supply to air conditioner is off. Before maintenance, it is necessary to cut off the
power and discharge the capacitor power which used in the air conditioner. If it is a must to need the
power supply during the maintenance, it is necessary to do ongoing leak detection at the most dangerous
position/point in order to avoid potential danger.
 Check the warning labels on the air conditioner whether are in good condition. It is necessary to replace
the damaged or smeared warning labels.
3). Leak inspection before maintenance
Before maintenance, use the leak detector or concentration detector (pump-type) recommended by
the corresponding air conditioner manufacturer to check the air conditioner leak or not.
Warning
If leak may exist, it is necessary to move all the fire out from the site or extinguish fire and then
immediately shut off the air conditioner. Meanwhile, it is necessary to make sure well-ventilated.
4). Safety principles during the maintenance
 At the time of maintenance, it is necessary to ensure well-ventilation on the site.
 It is prohibited to use fire including welding, smoking or other purposes. It is prohibited to use mobile
phones.
 At the time of maintenance, if the relative humidity is lower than 40%, it is necessary to wear anti-
static clothing and gloves.
 If the combustible refrigerant is found leaking during the maintenance, it is a must to immediately take
forced ventilation and plug up the leak source.
 If the product is damaged to the extent that it is a must to open the refrigerating system for
maintenance, it is a must to carry the product back to the maintenance station for maintenance. (It is
prohibited to weld the refrigerant pipe and do other operations on the user's site.)
 It is necessary to return the air conditioner to its initial state if it is necessary to provide visiting service
again due to lacking spare part during the maintenance. Moreover, it is a must to ensure that the
refrigerating system is in secure ground connection.
 If it is necessary to provide visiting service with a refrigerant cylinder, the volume of refrigerant filled in
such refrigerant cylinder should not exceed the stipulated value. When such cylinder is stored in a
vehicle or placed on the installation or maintenance site, it is necessary to place it vertically and
securely and keep it away from any place where there is any heat source, combustion source,
radiation source or electrical equipment.
5). Requirements for the site of maintenance-station
 The maintenance location should be well-ventilated, with leveled ground and not in a basement.
 The maintenance should be divided into welding and non-welding areas both of which should be
labeled clearly. There should be a certain safety distance between the two areas. The maintenance
location should be equipped with ventilating and air-exhausting equipment to prevent the refrigerant
gas from aggregating.
 It is necessary to provide some relevant instruments such as combustible refrigerant leak detector
and have a leak detecting instrument management system. It is necessary to confirm that the leak
detector can work normally before maintenance.
 The main power switch should be set outside the maintenance location and equipped with protective
(explosion-proof) devices.
Air Conditioner Service Manual
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