Emerson Liebert InteleCool 2, User Manual

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Introduction
3
1.3.1 Refrigeration System Options
Low Pressure Switch and Low Pressure Bypass Timer
Low Pressure Switch: Used to protect the Liebert InteleCool2 if the evaporator blower fails, the air
filter becomes clogged, the refrigeration circuit malfunctions or if there is loss of refrigerant. The low
pressure switch is activated when the suction pressure drops below its cutout setting. When
activated, the low pressure switch inhibits operation of the compressor and condenser fan. The switch
will automatically reset once the system pressure rises above its cut-in setting.
Low Pressure Bypass Timer: Also known as the Condenser Low Ambient Control or Winter Start
Option), the low pressure switch is used to start the system when the outdoor temperature is low. A
few minutes after startup, the low pressure switch resumes normal operation. This option can be used
for applications down to 50°F (10°C). For control down to -20°F (-28.9°C), use the T-pack1 or T-pack2.
T-pack1
This option provides a Low Pressure Switch, a Low Pressure Bypass Timer (described above), and a
Fan Cycle Control. This option package is one of the preferred control packages for
telecommunication industry applications.
The Fan Cycle Control, also known as the Condenser Fan Cycling Control, consists of a reverse-acting
pressure switch. When the outdoor temperature is low, the pressure switch cycles the condenser fan
to maintain discharge pressures that will allow the systems to function. It is to be used when the
outdoor ambient temperature is lower than 50°F (10°C) down to -20°F (-28.9°C).
T-pack2
This option includes a Low Pressure Switch, a Low Pressure Bypass Timer (described above), and an
adjustable Fan Cycle Control, which acts as described in the preceding paragraph, except that it is
adjustable. This option package is one of the preferred control packages for telecommunication
industry applications.
1.4 Ancillary Components
Wall-Mounted Thermostat
The thermostat provides for heating/cooling application with separate fan control. Supplied with a
thermostat sub-base.
Indoor Supply/Return Grilles
The supply grille is an aluminum louvered, double deflection type grille allowing user adjustment of
direction of air distribution. The return grille is an aluminum louvered, fixed, single-deflection style
grille.
Additional Spare Filters
Additional sets of the MERV 7 efficiency filters based on ASHRAE standard 52.2 (20% based on
ASHRAE standard 52.1) may be selected.
1.5 Accessories
Liebert Dual Unit Control
The hinged-cover, dual unit control has a two-stage heat/cool thermostat with individual heating and
cooling setpoints, adjustable interstage differentials, and bimetallic elements. The control features a
solid state timer with 1-2-4-8 day sequence. Unit lead selector, Unit 1 & 2 power-on LEDs, Unit 1 or 2
lead unit LEDs, 48 hour program save on loss of power, industry-standard connections and 24V power
from each unit. The DUC provides auto sequencing and displays on-status and operating-status
parameters.