724-746-5500 | blackbox.com
Page 16
724-746-5500 | blackbox.com
Chapter 1: Introduction
Figure 1-3 depicts a typical internal layout and identifies the major components of a typical Cold Row CW (CRCW-24) unit. The
location of some components may vary.
CW valve
Electric box
Air filters
T/H sensor
Supply/return pipe
transition plate
Humidifier
drain pump
Temperature
sensors (hidden
from view)
Disconnect
switch
Swing-out
hinge
Float switch
Drain pans
EC fan (3)
Caster
housing (4)
Level adjustment
screw (4)
Humidifier
Coil
Condensate
pump
Figure 1-3. Typical internal layout: Cold Row CW (CRCW-24).
NOTE: In Figure 1-3, cabinet access panels are removed to show internal parts.
1.5.1 Electrical Compartment
The electrical components are protected inside an electric box located behind the rear access panel. The electric box cover is
safety interlocked with the service disconnect switch (See Figure 1-2), preventing the cover from being opened when the switch is
in the On position. The switch must be turned Off to gain access to the electrical compartment.
The service disconnect switch may be used to turn the unit off for emergency shutdown or when routine maintenance is
performed. The handle of the switch locks in the “Off” position to prevent unintended operation.
1.5.2 Circuit Breakers/Motor Start Protectors
Cold Row units incorporate state-of-the-art component protection using motor start protectors and circuit breakers. If an overload
occurs, you must manually reset the switches after clearing the overload condition.
1.5.3 Coils
Cooling coils are constructed of aluminum finned/copper tube. The coils are leak tested and cleaned before installation by the
factory. Condensate drain pans are provided to collect water condensed by the coils. A condensate pump empties the drain pans
and directs the water to a pipe stub located either at the top or the bottom of the A/C unit depending on the piping
configuration (see Section 2.7.1 and 2.8.1.1).
A float switch in the lower condensate pan detects if the water level rises. If the condensate pan fails to drain, the float switch
signals the controller to sound an alarm and turn off the compressor and the fans.