McQuay MDS030AR Applications Manual page 87

4.3.8 Air Leak Gap Checking
Test 1 (when the pressure reduces)
Hearing use your ear to find it out.
Touching use your hand to find it out.
Soap water
Test 2 (when step 1 can not find out , then the following should be adopted)
Reduce nitrogen pressure to 3.0kg/cm
Charge the nitrogen with R22 to 5.0kg/cm
Use haloid lamp, alkyl detector or electric controller to check;
If still can not find the air leak gap, then the pressure should be charged to 28.0kg/cm
check it again;
(The pressure can not be more than 28.0kg/cm
NO.1
Outdoor unit
Valve
A B
Indoor unit
Notes: If the pipe is too long, it should be divided to sections to test as follows:
Indoor side
Indoor side + vertical pipes
Indoor side + vertical pipes + outdoor piping assembly
4.3.9 Copper Pipe Insulation
Refrigerant piping
assembly
Material
All the insulation material should be strong enough to insulate the pipe.
For example, polyethylene is a good insulation material.
key points
Some areas such as welding area, enlarged port area and flange area can be insulated only after
the air leak test. Pay attention to the unit model and the running condition, for some gas pipe and
liquid pipe are all needed to be insulated.
use soap water to find it out.
2
;
NO.2
Vacuum pump
C D
pipe insulation
Design & installation Guide For McQuay MDS Multi System
2
;
2
).
Refrigerant
Gauge
air leak test
2
and
Nitrogen bottle
pipe insulation
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