Air Source Screw Water Chiller Unit – Installation Operation and Maintenance Manual
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.3.2.10 Pipe Blowing
1)
Blowing of copper pipe
(1) Principle of operation: Blow pressure gas into pipes (raw material pipes or soldered components)
to remove the dust and water inside the pipes. (Solid impurities cannot be removed; therefore,
relevant protective measures must be taken during implementation.)
(2) Purpose
①
Remove the oxide power or part of the oxide skin inside the copper pipe.
②
Remove the impurities and moisture inside the pipe.
(3) Reason
If pipe blowing is not performed, solid impurities and water inside the pipes cannot be removed.
As a result, ice plug, filth blockage, compressor failure, and other severe problems may occur.
2)
Preparation
(1) Install the pressure regulator valve on the nitrogen cylinder. (Use nitrogen instead of any other
gas, because Polyter afuoroethyenea or carbon dioxide may cause condensation, and oxygen
may cause explosion.)
(2) Use a gas tube to connect the outlet of pressure regulator valve and the inlet of gas pipe/liquid
pipe of outdoor unit.
(3) Block the joint of copper pipe with a blind plug and blow each branch pipe. During soldering,
blow and clean each pipe after the pipe is soldered. When all pipes are soldered, clean the pipe
system again.
(4) Open the valve of the nitrogen cylinder and set the regulator valve to 5 kgf/cm2.
3)
Operation procedure
(1) Use proper plugging materials (for example, a wood brick wrapped with cotton cloth) to block the
end of the major air pipe of indoor unit.
(2) Release the plugging materials suddenly when you cannot resist the pressure in the pipe. Until
now, the pipe is blown and cleaned for one time.
Then, repeat step 1 and step 2 to blow and clean the pipe many times.
(3) Put a piece of cotton cloth loosely near the pipe end. In this way, you can detect the dirt and
