10
5
Welding Refrigerant Pipes
Laying the Engineering Pipe
5.1
Wall
Pipe
Pipe support
1. When outdoor unit is installed horizontally, the outdoor unit and the low-temperature component
must be at the same horizontal plane. When outdoor unit is installed vertically, the installing
horizontal plane of outdoor unit must not be lower than the installing horizontal plane of low-
temperature component, and the height difference cannot exceed 1.5 m.
2. When calculating the height difference, the compressor base is regarded as the baseline for the
indoor unit, and the condenser top is regarded as the baseline for the outdoor unit.
3. The inverted trap should be higher than the top copper pipe of the condenser.
4. When the indoor unit is higher than the outdoor unit, the maximum height difference is 8 m. When
the indoor unit is lower than the outdoor unit, the maximum height difference is 30 m.
5. When welding pipes, ensure that the pipes are dry. You are recommended to weld the pipes
between the indoor and outdoor units, then connect the two ends of the pipe to the indoor unit and
outdoor unit.
6. Use a rubber hose to connect the nitrogen cylinder which connecting the reducing valve and the
end of the copper pipe, then fill nitrogen at 0.03
–0.05 MPa into the copper pipe to avoid internal
oxidation.
7. After the pipe in the middle is welded, charge nitrogen into the pipe from one pipe end to clear the
foreign matter inside.
8. Do not expose welding positions to the environment for a long time. Take sealing measures for
welding positions. If foreign matter exists at the welding position, rubber it out using non-water
alcohol or damp cloth before the welding.
9. Take protective measures, such as spreading a piece of wet cloth, around the welding position, to
avoid burning the bottom panel, top panel, side panel, internal components, needle valves, other
pipes, thermal insulation foam, power cables, labels, and tags.
Discharging Nitrogen of Indoor Unit
5.2
NetCol8000-A045/A090 Downflow
Exhaust nitrogen from the three needle valves.
NetCol8000-A045 Upflow
