1
3
. Installation
Refrigerant pipe welding and safety information Important
information for refrigerant pipe work
•
Make sure there is no moisture inside the pipe.
•
Make sure there are no foreign substances and impurities in the pipe.
•
Make sure there is no leakage.
•
Make sure to follow the instruction when welding or storing the pipe.
Nitrogen flushing while brazing (DVM Hydro unit)
•
When brazing the refrigerant pipes, flush them with nitrogen gas as shown in the picture.
•
If you do not perform nitrogen flushing when brazing the pipes, oxide may form inside the pipe and can cause damage to the
important parts such as compressor and valves etc.
•
Adjust the flow rate of the nitrogen flushing with a pressure regulator to maintain 0.05 m
3
/h (1.77 ft
3
/h) or less.
•
When brazing the pipes on the connection port, cover the valve with wet cloth before brazing (to protect the parts within the valve)
Brazed part
Nitrogen
Copper pipe [Φ6 .35 (1/4")]
Stop valve
Taping
High pressure hose
Nitrogen
Wet cloth
Gas side
(brazed)
Flowmeter
Φ 6 .35 (1/4")
Pressure regulator
Direction of the pipe when brazing
•
Direction of the pipe should be headed downward or sideways when brazing.
•
Avoid brazing the pipe with pipe direction heading upward.
Upward
Side
Downward
