Emerson ITR manual Air-Cooled, Self-Contained Systems-Standard Features

Air-Cooled System—Standard and Optional Features

7.0AIR-COOLED SYSTEM—STANDARD AND OPTIONAL FEATURES

7.1Air-Cooled, Self-Contained Systems—Standard Features

7.1.1Pump Down Control

The compressor pump-down control is accomplished by a liquid-line solenoid valve used in conjunc- tion with a low pressure switch.

7.1.2Condenser

The Liebert manufactured low profile, direct drive propeller fan type air-cooled condenser provides quiet, efficient operation.

It is constructed of aluminum with a copper tube and aluminum fin coil for corrosion resistance. An integral, factory wired and tested control panel reduces installation time.

7.1.3Fan Speed Control

The winter control system features a variable speed motor and a specially designed solid-state fan speed control transducer.

The transducer senses refrigerant pressure and varies the speed of the fan motor to maintain con- stant condensing temperature and system capacity. This system permits operation at ambient tem- peratures as low as -20°F (-29°C).

7.2Air-Cooled, Self-Contained Systems—Optional Features

7.2.1Liebert Lee-Temp Winter Control Condenser

The Liebert Lee-Temp winter control system’s heated receivers permit startup and positive head pressure control at ambient temperatures as low as -30°F (-34.4°C). The Liebert Lee-Temp package includes insulated receiver, a pressure relief valve, three-way head pressure control valves, and rota- lock valves (see Figure 5 below).

7.2.2Quiet-Line Condensers

Quiet-Line Condensers can help your facility meet the strictest noise codes, and do so at less cost than traditional condensers with acoustical shielding.

Figure 5 Air-cooled condenser with Liebert Lee-Temp

Air-Cooled Condenser

Liebert Lee-Temp

Package (optional)

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