Emerson ITR manual Direct Expansion Self-Contained Systems

Electrical Data

2.1.12Plenum

The unit shall be supplied with a (2 way) (3 way) (4 way) (low-profile, cold-aisle) air discharge ple- num. The plenum shall be 18 in. (457mm) high or less, insulated and powder painted the same color as the room unit.

2.1.13Disconnect Switch, Locking Type

The manual disconnect switch shall be mounted in the high voltage section of the electrical panel. The switch shall prevent access to the high voltage electrical components until switched to the “OFF” posi- tion.

2.1.14Remote Sensors (Required for Select Applications)

The unit shall be supplied with remote temperature and humidity sensors. The sensors shall be con- nected to the unit by a 30 ft. (9m), 60 ft. (18m), 90 ft. (27m), 120 ft. (36m), 150 ft. (45m) shielded cable.

2.1.15Remote Sensor Installation Location

The remote temperature and humidity sensor should be installed in the cold aisle in front of the equipment to be cooled. It should be mounted at the farthest point from the cooling unit that supply air needs to reach but still within the unit’s area of influence. The sensor should be installed at the highest point that equipment will draw in cooled air.

2.1.16Firestat (Optional)

The firestat shall immediately shut down the system when high temperatures are detected. The fir- estat shall be mounted in the electrical panel with the sensing element in the return air.

2.1.17Smoke Detector (Optional)

The smoke detector senses the return air, shuts down the unit upon detection, and sends visual and audible alarm. Dry contacts are available for a remote customer alarm. This smoke detector is not intended to function as or replace any room smoke detection system that may be required by local or national codes.

2.1.18Condensate Pump

The condensate pump shall have the capacity of ____ GPH (l/h) at ____ ft. (m) head @ ____ V - ____ Hz. It shall be complete with (single) (dual) integral float switch, pump, motor assembly, and reservoir.

2.2Direct Expansion Self-Contained Systems

Direct Expansion Coil

The evaporator coil shall have _____ sq.ft. (sq. m) face area, _____ rows deep. It shall be configured as

V-frame and be constructed of copper tubes and aluminum fins and have a maximum face velocity of

_____ ft. per minute (m/s) at _____ CFM (CMH). The coil shall be provided with a stainless steel drain

pan.

Refrigeration System

The refrigeration system shall consist of a high efficiency scroll compressor, hot gas bypass, pressure safety switches, externally equalized expansion valve, filter drier, refrigerant sight glass and mois- ture indicator.

2.2.1Air-Cooled Self-Contained Systems

Pump Down Control

A liquid line solenoid valve shall be provided for pump down control.

Crankcase Heater

A crankcase heater shall be provided for additional system protection from refrigerant migration dur- ing off cycles.

Propeller Fan Condenser (Standard)

The Liebert manufactured air-cooled condenser shall be the low profile, slow speed, direct-drive, pro- peller-fan type. The condenser shall be constructed of aluminum and contain a copper tube, alumi- num fin coil with an integral electric control panel. The system shall be designed for _____ °F (°C) ambient. The air-cooled condenser shall have a _____ Volt, _____ phase, ____ Hz power supply.

58