[. . . ] Another important consideration in selecting a location for the unit(s) is the angle to obstructions. Either side adjacent the valves can be placed toward the structure provided the side away from the structure maintains minimum service clearance. Corner installations are strongly discouraged.
CAUTION
Hazards or unsafe practices which may result in property damage, product damage, personal injury or death.
WARNING
HIGH VOLTAGE!
Disconnect ALL power before servicing. Failure to do so may cause property damage, personal injury or death.
WARNING
ONLY individuals meeting the requirements of an "Entry Level Technician" as specified by the Air Conditioning and Refrigeration Institute (ARI) may use this information. [. . . ] · Never fill a cylinder more than 80% full of liquid refrigerant. · Never add anything other than R-22 to an R-22 cylinder or R-410A to an R-410A cylinder. The service equipment used must be listed or certified for the type of refrigerant used. Never use a cylinder as a platform or a roller.
1 1/2 2 2 1/2 3 3 1/2 4 5 5/8 5/8 5/8 3/4 3/4 7/8 7/8
1/4 1/4 1/4 3/8 3/8 3/8 3/8
3/4 3/4 3/4* 3/4** 7/8** 1 1/8 1 1/8
3/8 3/8 3/8 3/8 3/8 3/8 3/8
3/4 3/4 7/8 7/8** 1 1/8 1 1/8 1 1/8
3/8 3/8 3/8 3/8 3/8 3/8 3/8
* 7/8" required for full ratings ** 1 1/8" required for full ratings *** Lines greater than 74 feet in length or vertical elevation changes more than 50 feet refer to the Remote Cooling Service Manual or contact your distributor for assistance.
2
Liquid Line Suction Line
1. The ends of the refrigerant lines must be cut square, deburred, cleaned, and be round and free from nicks or dents. Any other condition increases the chance of a refrigerant leak.
Mounting the evaporator coil above the condensing unit will require an inverted loop in the suction line adjacent or near the connection to the evaporator. The top of the loop must be slightly higher than the top of the coil.
2. "Sweep" the refrigerant line with nitrogen or inert gas during brazing to prevent the formation of copper-oxide inside the refrigerant lines. The POE oils used in R-410A applications will clean any copper-oxide present from the inside of the refrigerant lines and spread it throughout the system. After brazing, quench the joints with water or a wet cloth to prevent overheating of the service valve. If the paint of the steel filter drier has been burned or chipped, repaint or treat with a rust preventative. This is especially important on suction line filter driers which are continually wet when the unit is operating. Kinked or dented lines will cause poor performance or compressor damage. Do NOT make final refrigerant line connection until plugs are removed from refrigerant tubing. NOTE: Before brazing, verify indoor piston size by checking the piston kit chart packaged with indoor unit.
Mounting the condensing unit above the evaporator coil will require oil traps at equal intervals along the suction line. Install 1 oil trap for a height difference of 1525 feet between indoor and outdoor units. Install 2 oil traps for a difference of 26-50 feet, 3 for 51-100 feet, and 4 for 101-150 feet.
Insulation is necessary to prevent condensation from forming and dropping from the suction line. In severe conditions (hot, high humidity areas) 1/2" insulation may be required. Insulation must be installed in a manner which protects tubing from damage and contamination. Where possible, drain as much residual compressor oil from existing systems, lines, and traps; pay close attention to low areas where oil may collect. NOTE: If changing refrigerant types, ensure the indoor coil and metering device is compatible with the type of refrigerant being used; otherwise, the indoor coil must be replaced.
Leak Testing (Nitrogen or Nitrogen-Traced)
WARNING
To avoid the risk of fire or explosion, never use oxygen, high pressure air or flammable gases for leak testing of a refrigeration system.
Burying Refrigerant Lines
If burying refrigerant lines can not be avoided, use the following checklist. Enclose all underground portions of the refrigerant lines in waterproof material (conduit or pipe) sealing the ends where tubing enters/exits the enclosure. [. . . ] Systems with TXV application should have a subcooling and superheat of 9 ±3 ºF. If subcooling and superheat are low, adjust TXV to 9 ± 3ºF then check subcooling. If subcooling is low and superheat is high, add charge to raise subcooling to 9 ± 3ºF then check superheat. If subcooling and superheat are high, adjust TXV valve to 9 ± 3ºF then check subcooling. [. . . ]