Desert Aire SelectAire Plus SP Series, Инструкция по установке и эксплуатации

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Desert Aire - SP Manual
2.15.3 Refrigeration Piping Reassembly (when applicable)
There will be copper tubing segments with couplings previously installed to each segment in the
Cabinet Reassembly section. To properly braze these sections:
• Remove grease or oil first using a dry towel and solvent sprayed onto the towel if
necessary.
• Remove dirt and oxidation using a Scotch-Brite pad, tube brush, or a wire wheel. Clean
the tube end to a depth about 1/2” greater than the insertion depth of the tube.
• Flow nitrogen through the braze assembly during brazing to eliminate the formation of
oxides inside the tubing. The presence of oxygen creates when exposed to
brazing temperatures. Flowing nitrogen through assemblies displaces oxygen which keeps
internal surfaces oxide-free.
• There should be one inlet and one outlet when flowing nitrogen through an assembly.
• Adapt the nitrogen hose to the inlet side of the assembly. The adapter should seal the inlet
opening tightly.
• Verify nitrogen flows through all parts of the assembly being brazed.
• Set nitrogen flow to about 15 scfh (standard cubic feet / hour). Braze the line connections
together with Sil-Phos 5 brazing alloy once fittings and copper tubing has been set in
place.
• Wrap critical components such as valves with a cool, damp rag to reduce possibilities of
heat damage.
• Braze the line connections together with Sil-Phos 5 brazing alloy once fittings and copper
tubing has been set in place.
• Using a cool, damp rag, wipe the outside of the joint taking care not to get water inside the
assembly. Continue cooling until assembly is cool enough to touch.
• Wipe off all flux residue.
• Once braze joint is cooled down nitrogen may be removed.
• Cap all open parts of the assembly or circuit.
2.15.4 Refrigeration System Evacuation / Preparation for Operation (when applicable)
• Pressure test each reconnected refrigeration lines to insure leak-tight connections.
- Install a pressure gauge on the system or downstream of the regulator valve on a tank of
nitrogen.
- Let system sit for 10 minutes. Ensure that pressure has not decreased after this time.
- Relieve the pressure.
• Evacuate the section of tubing between the ball valves on each reconnected refrigeration line
splice.
- Verify pressure is removed using Schrader core depressors.
- Connect and turn on pump.
- The refrigeration system must stay below 500 microns after 10 minutes of decay testing.
The recommended starting point to pass the decay test is around 350 microns.
• After successful leak testing and evacuation, open all ball valves interconnecting the unit sections.