mechanical
Installation requirements
Refrigerant Piping (Air-Cooled Units Only)
Reference industry recommendations for
The charge is contained by a continuous loop of both hot gas and liquid lines. You must cut the loop for connection to discharge and liquid lines. See Figure I-
WARNING:
Hazard of Explosion and Deadly Gases!
Never solder, braze or weld on refrigerant lines or any unit com- ponents that are above atmo- spheric pressure or where refrigerant may be present. Always remove refrigerant by fol- lowing the guidelines estab- lished by the EPA Federal Clean Air Act or other state or local codes as appropriate. After refrig- erant removal, use dry nitrogen to bring system back to atmospheric pressure before opening system
for repairs. Mixtures of refriger- ants and air under pressure may become combustible in the pres- ence of an ignition source leading to an explosion. Excessive heat from soldering, brazing or weld- ing with refrigerant vapors present can form highly toxic gases and extremely corrosive acids. Failure to follow all proper safe refrigerant handling prac- tices could result in death or seri- ous injury.
Brazing Procedures
Proper brazing techniques are essential when installing refrigerant piping. Keep the following factors in mind when making sweat connections.
1.When heating copper in the presence of air, copper oxide forms. To prevent copper oxide from forming inside the tubing during brazing, sweep an inert gas, such as dry nitrogen, through the tubing. Nitrogen displaces air in the tubing and prevents oxidation of interior surfaces. A nitrogen flow of one to three cubic feet per minute is sufficient to displace the air. Use a pressure regulating valve or flow meter to control the flow.
2.Ensure tubing surfaces that require brazing are clean and the ends of the tubes are carefully reamed to remove any burrs.
3.Make sure the inner and outer tubes of the joint are symmetrical and have a close clearance, providing an easy slip fit. If the joint is too loose, the tensile strength of the connection will be significantly reduced. Make the overlap distance equal to the inner tube diameter.
4.Wrap the body of each refrigerant line component with a wet cloth to keep it cool during brazing. Excessive heat can damage the components.
5.If using flux, apply it sparingly to the joint. Excess flux will contaminate the refrigerant system.
6.Apply heat evenly over the length and circumference of the joint, making sure the entire joint becomes hot enough to melt the brazing material.
7.Begin brazing when the joint is hot enough to melt the brazing rod. The hot copper tubing, not the flame, should melt the rod.
8.Continue to apply heat around the joint circumference until the brazing material is drawn into the joint by capillary action, making a mechanically sound and
9.Visually inspect the connection after brazing to locate any pin holes or crevices in the joint. Use a mirror to inspect connections that are difficult to see.
Electrical Requirements
Follow these guidelines, referring to unit wiring diagrams and supply power dimensional information to ensure correct electrical requirements at the installation site. Reference supply power wiring locations on unit submittals orin the “Dimensions and Weights” section. Specific unit wiring diagrams are provided on each unit. Use these diagrams for connections or trouble analysis.
Unit Wiring Diagrams
Specific unit wiring diagrams are provided on the inside of the control panel door. Use these diagrams for connections or trouble analysis.
Figure
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