These specifications describe requirements for an
environmental control system. The system shall be
designed to maintain temperature and relative
humidity conditions within the room. The manufac-
turer shall design and furnish all equipment to be
fully compatible with heat dissipation requirements
of the site.
The environmental control system shall be a Liebert
Challenger 3000 factory assembled unit. Standard 60
Hz units shall be UL listed and CSA (NRTL-C) certi-
fied. It shall be specifically designed for service from
the front of the unit. The system shall be designed for
draw-through air arrangement to insure even air dis-
tribution to the entire face area of the coil.
Each system shall be capable of handling ____ CFM
(CMH) at ____inches (mm) of water external static
pressure with (down discharge air flow) (up dis-
charge air flow with front return or up discharge air-
flow with rear return) pattern. It shall have a total
cooling capacity of ____ BTU/HR (kW), sensible cool-
ing capacity of ____ BTU/HR (kW), based on the
entering air condition of °F (°C) dry bulb, and ____ °F
(°C) wet bulb. These units are to be supplied with
____ Volt, ____ phase, ____ Hz power supply. The
humidifier shall have a capacity of ____ lbs/hr (kg/h).
Reheat shall have a capacity of _____ BTU/HR (kW).
The main fan shall be ____ HP (kW).
Submittals shall be provided with the proposal and
shall include: Single-Line Diagrams; Dimensional,
Electrical, and Capacity data; Piping and Electrical
Connection Drawings.
The frame shall be constructed of MIG welded tubu-
lar and formed steel. All frame components shall be
finished in a black, powder-coat finish to protect
against corrosion. The exterior panels shall be
(20 gauge)/(18 gauge) steel and shall be powder
coated with ____ color paint. The panels shall be
insulated with a minimum 1 in. (25.4mm), 1-1/2 lbs.
(0.68 kg) density fiber insulation. Front and side
panels shall have captive, 1/4 turn fasteners.
The cabinet shall be designed so that all components
are serviceable and removable from the front of the
unit.
The fan shall be the centrifugal type, double width,
double inlet. The shaft shall be heavy duty steel with
self-aligning ball bearings with minimum life span of
100,000 hours.
The fan motor shall be 1750 RPM and mounted on an
adjustable base. The drive package shall be sized for
200% of the fan motor horsepower, and equipped
with an adjustable motor pulley. The fan/motor
assembly shall be mounted on (vibration isolators)
(solid base). The fan shall be located to draw air over
the coil to ensure even air distribution and maximum
coil performance.
High Efficiency Motor (Optional)
The fan motor shall be a ____ HP (kW) high effi-
ciency motor with a full load efficiency of ____ %.
The filter shall be____ inches (mm) thick and rated
not less than _____ % (20%, 30%, 40-45%, 60-65%)
efficiency based on ASHRAE 52.1.
Prefilter (Optional)
The prefilter shall be 2 in. (50.8mm) thick with an
efficiency of 20% based on ASHRAE 52.1.
The Advanced control processor shall be micropro-
cessor based with a front monitor LCD display panel
and control keys for user inputs. The controls shall
be menu driven with on-screen prompts for easy user
operation. The system shall allow user review and
programming of temperature and humidity set-
points, alarm parameters, and setup selections
including choice of control type. A password shall be
required to make system changes. For all user selec-
tions, the range of acceptable input (temperature,
humidity, or time delay) shall be displayed on the
monitor screen. The system shall provide monitoring
of room conditions, operational status in % of each
function, component run times, date and time, and
four analog inputs from sensors provided by others.
Control
The control system shall allow programming of the
following room conditions:
Temperature Setpoint 65 to 85°F (18-29°C)
Temperature Sensitivity +1 to +9.9°F (0.6 to
5.6°C) in 0.1° increments
Humidity Setpoint 20 to 80% RH
Humidity Sensitivity +1 to +30% RH
All setpoints shall be adjustable from the individual
unit front monitor panel. The microprocessor can be
set within these ranges, however, the unit may not
be able to control to extreme combinations of temper-
ature and humidity.
DISCONTINUED
PRODUCT
