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5. PIPE INSTALLATION-1
5.1. Opening a knock out hole
CAUTION
Be careful not to deform or scratch the panel while opening the knock out holes.
To protect the piping insulation after opening a knock out hole, remove any burrs from the edge of the hole. It is recommended to apply rust prevention paint to the edge of the hole.
• Pipes can be connected from 3 directions, front, lateral side and bottom. (Fig. A)
• When connecting at the bottom, remove the service panel and piping cover on the front of the outdoor unit, and open the knockout hole provided at the bottom corner of the piping outlet.
Fig. A
Service panel
94 21
60 12 14
Top view of the base
21 92
Unit: mm
CAUTION
For brazing material, use phosphor copper that does not require fl ux. Do not use fl ux to braze pipes. If the fl ux is the chlorine type, it will cause the pipes to corrode.
Furthermore, if the fl ux contains fl uoride, it will adversely affect the refrigerant pipe system such as by degrading the refrigerant.
If fl uoride is contained, quality of refrigerant deteriorates and affects the refrigerant piping system.
5.3. Pipe connection
5.3.1. Bending pipes
CAUTION
To prevent breaking of the pipe, avoid sharp bends. Bend the pipe with a radius of curvature of 100 mm to 150 mm.
If the pipe is bent repeatedly at the same place, it will break.
• If pipes are shaped by hand, be careful not to collapse them.
• Do not bend the pipes at an angle of more than 90°.
• When pipes are repeatedly bent or stretched, the material will harden, making it dif fi cult to bend or stretch them anymore.
• Do not bend or stretch the pipes more than three times.
5.3.2. Removing the pinch pipe
WARNING
Remove the pinch pipe only when the internal gas is completely drained as shown on the below instructions.
If gas still remains inside, the piping may crack if you melt the brazing filler metal of the junction area with a burner.
Before connecting the piping, remove the pinch pipe in accordance with the following instructions:
1) Verify that the liquid side and gas side 3-way valves are closed.
2) Cut the end of the liquid side and gas side pinch pipe and vent the gas inside the pinch pipe.
3) After all the gas is vented, melt the brazing filler metal on connecting part using a torch and remove the pinch pipe.
3-way valves
Front connection Lateral connection Bottom connection
• It can be installed as shown on “Fig. B” cutting out the 2 slits as indicated on “Fig. C”.
(When cutting slits, use a steel saw.)
Fig. B Fig. C
Slit
Slit
Bottom connection
5.2. Brazing
CAUTION
If air or another type of refrigerant enters the refrigeration cycle, the internal pressure in the refrigeration cycle will become abnormally high and prevent the unit from exerting its full performance.
Apply nitrogen gas while brazing the pipes. If a pipe is brazed without applying nitrogen gas, an oxidation fi lm will be created.
This can degrade performance or damage the parts in the unit (such as the compressor or valves).
Pressure regulating valve
Cap
Nitrogen gas pressure: 0.02 MPa
(= pressure felt suf fi ciently on the back of the hand)
Nitrogen gas
Brazing area
End of pinch pipes
Pinch pipes
5.3.3. Pipe connection
CAUTION
Seal the pipe route hole with putty (locally purchased) such that there are no gaps.
Small insects or animals that are trapped in the outdoor unit may cause a short circuit in the electrical component box.
After completing all the pipe connection by brazing, perform the indoor unit pipe connection with a flare joint.
When removing the pinch pipe or brazing the joint pipe, carry out the work while cooling down the 3-way valve sufficiently.
• Braze the joint pipe onto the 3-way valves at the liquid and gas side. Install the joint pipe appropriately so that it can be connected easily with the main pipe.
• Braze the joint pipe at the liquid and gas side with the main pipe.
* Be sure to supply nitrogen when brazing.
En-6
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