20
Fig. 28 —
Control Box Layout
Step 6 — Make Final Preparations
1. Power unit(s) off (open unit electrical disconnect) and install
lockout tags on all power supplies to the unit.
2. Install field-supplied thermostats and perform all other final
wiring needed. Ensure all electrical connections are secure.
3. Perform final visual inspection. All equipment, ductwork,
and piping should be inspected to verify all systems are com
-
plete and properly installed and mounted, and that no debris
or foreign articles are left in the unit(s). Clean dirt, dust, and
other construction debris from unit interior. Assess fan wheel
and housing and clean if necessary.
4. Verify drain line is properly and securely positioned and that
the line is clear. Pour water into drain to verify operation.
5. Rotate fan wheel by hand to be sure it is free and does not rub
housing.
6. Install the filter into the filter frame. If field-supplied filters
are used, verify filter size (see Table 4).
Table 4 —
Filter Sizes
7. Ensure all panels and filters are installed before checking fan
operation. Turn on power to the unit.
8. Inspect the fan and motor operation.
START-UP
Before beginning any start-up operation, the start-up personnel
shall familiarize themselves with the unit, options and accessories,
and control sequence to understand the proper system operation.
All personnel shall have a good working knowledge of general
start-up procedures and have the appropriate start-up and
balancing guides available for consultation.
The building must be completely finished including doors,
windows, and insulation. All internal walls and doors should be
installed. In some cases, the interior decorations and furniture may
influence overall system performance. The entire building should
be as complete as possible before beginning any system balancing.
Cooling/Heating System
Prior to the water system start-up and balancing, flush the
chilled/hot water systems to clean out dirt and debris which may
have collected in the piping during construction. During this pro
-
cedure, all unit service valves must be in the closed position to
prevent foreign matter from entering the unit and clogging the
valves and metering devices. Strainers shall be installed in the
piping mains to prevent such material from entering units during
normal operation.
During system filling, air venting from the unit is accomplished
by the use of the standard, manual air vent fitting, or the option
-
al, automatic air vent fitting installed on the coil. (See Fig. 29).
Manual air vents are basic Schrader valves that could be
accessed from the coil side of the unit and are located between
the coil header and end sheet. To vent the air from the coil, de
-
press the valve until the air has vented the coil. When water be
-
gins to escape through the valve, release the valve.
Automatic air vents may be unscrewed one turn counterclockwise
to speed initial venting, but should be screwed in for automatic
venting after start-up operations.
Motor
Control
Board
Equipment
Ground
Terminal
Terminal Strip
Wiring Diagram
(inside the door)
Serial Plate
Wrapper
Contactors
Transformer
Electric Heater
Limit Switch
Knob
Heater Fuses
Auxillary Control Box
(supplied when ordered
with
3-speed
controls
and/or service light)
Service Light
Strip
Battery
Charger
Service Light
Battery
Door Switch
Bonded
Ground
24v Control
Fuse
Disconnect Switch
NOTE: Above is the example of Control box for Size 20 unit with electric heat, disconnect switch and service light.
42DH/DV
UNIT SIZE
FILTER
QUANTITY
NOMINAL FILTER SIZES
in. (mm)
06
1
16-1/2 x 24 (419 x 610)
08
1
16-1/2 x 24 (419 x 610)
10
1
18-1/4 x 33 (464 x 838)
12
1
18-1/4 x 33 (464 x 838)
16
2
18-1/4 x 21-1/2 (464 x 546)
20/22
2
20-1/2 x 22 (521 x 559)
30
2
29 x 22 (737 x 559)
