Split System Models
7.2.1Line Voltage
Line voltage electrical service is required for all condensing units at the location of the condensing unit. This power supply does not have to be the same voltage as the indoor unit. This separate power source may be 208, 230, 460 or 575V, 60 Hz; or 200, 230, or 380/415V, 50 Hz. A disconnect switch is required and must be mounted per local and national codes to isolate the unit for maintenance.
7.2.2Low Voltage
The control cable between the condensing unit and the evaporator unit is connected between terminals 1,2 and 3 on the terminal strip in the evaporator unit and the condensing unit control box. A fourth wire is required on systems with hot gas bypass. NEC Class 1 wiring is required. Glycol- cooled units also require a
7.3Piping Considerations
7.3.1 Refrigerant Loop
! WARNING
Risk of explosive discharge from
This unit contains fluids and gases under high pressure. Relieve pressure before working with piping.
NOTICE
Risk of improper refrigerant charge. Can cause equipment damage, environmental degradation and violation of national, state and local law.
Follow all applicable codes for handling refrigerant.
R22 and R407C are similar in
R407C refrigerant must be introduced and charged from the cylinder only as a liquid.
NOTICE
Risk of improper piping installation. Can cause contamination of hygroscopic oil with water.
When installing field piping, care must be taken to protect all refrigerant lines from the atmosphere, especially when using refrigerants, such as R407C which requires use of polyol ester oils. Do not allow the piping to stand open to air for more than 15 minutes. Units designed for R407C have a compressor that contains polyol ester oil, which is very hygroscopic; that is, it quickly absorbs water from the air. The longer the compressor piping is left open to air, the harder it will be to fully evacuate. If left open too long, the polyol ester oil may need to be replaced before achieving the required vacuum level.
NOTE
Complete all piping and evacuate lines before connecting quick connects when using an optional sweat adapter kit and field installed hard piping.
Follow all proper brazing practices including a dry nitrogen purge to maintain system cleanliness.
Liebert® Challenger 3000™ | 58 |