6
Step 8 — Make Duct Connections —
Install all duct-
work to and from unit in accordance with all applicable codes.
Duct construction must allow unit to operate within the limits of
the unit external static pressure as shown on job submittals.
Units designed to operate with ductwork may be damaged if
operated without the intended ductwork attached. Units config-
ured to bring in outside air should have some method of low
temperature protection to prevent coil freeze-up.
Insulate all ductwork as required. Use flexible connections
to minimize duct-to-duct alignment problems and noise trans-
mission where specified. Acoustic lining of main supply and
return duct should be considered for noise control. Noise trans-
mission will be reduced when return grilles are located as far as
possible from the unit.
Install ductwork, accessory grilles, and plenums so that they
do not restrict access to filter.
NOTE: Prevent dirt, dust, and debris from settling in unit
.
Step 9 — Install Mixing Box —
Mixing boxes are
preassembled from the factory. A linkage kit consisting of
2 crankarms, 2 swivels, and either a 25 in. (unit sizes 06-16) or
a 34 in. (unit sizes 20-40) length of
5
/
16
in. rod is provided for
field installation of the actuator.
To install the mixing box:
1. Assemble the mixing box base rails using the provided
hardware. The base rails are marked with identifying let-
ters. See Fig. 5.
2. Place unit on the base rails. Install mixing box and attach
to base rails using the no. 8 x
1
/
2
in. fasteners at the loca-
tions shown in Fig. 6.
3. Seal the connection between the mixing box and the re-
turn duct flange.
NOTE: Be careful not to tape or seal the filter access
panel.
Step 10 — Make Final Preparations
1. TURN POWER OFF. (Open unit electrical disconnect.)
2. Clean unit thoroughly. Remove dirt and debris from unit,
especially drain pan, drain line, motor and fan. Pour water
into drain pan to check that drain operates properly.
3. Rotate fan wheel by hand to be sure wheel is free and
does not rub housing. The 42BHE,BVE belt drives are
factory set at the speed required for the design specifica-
tions specified when ordered. These drives may be ad-
justed to achieve different speed by qualified personnel
during air system balancing. Refer to the Start-Up section
before energizing the unit. Check fan belt tension as de-
scribed in the Service section which follows.
4. Check that a clean air filter of proper type and size is in-
stalled in unit filter rack after commissioning. See Table 1
and Clean or Replace Air Filters section. Do NOT oper-
ate unit without filter.
5. Turn on water supply. Open all valves. Check for leaks.
Recheck pitch of suspended unit.
6. Vent all air from unit coil and related piping. If air vent is
manual, release air by turning air vent screw 1
1
/
2
turns
counterclockwise with screwdriver. When a steady
stream of water begins to escape, close valve. If vent is
automatic, trapped air will be released automatically. Vent
releases air slowly, usually dripping water into the drain
pan in the process.
Fig. 5 — Assemble Base Rails
a42-4164
a42-4165
CAUTION
The air vent provided on the unit is not intended to replace
the main system vents and may not release air trapped in
other parts of the system. Inspect the entire system for
potential air traps and vent those areas as needed. Some
systems may require repeated venting over a period of time
to properly eliminate air from the system. Failure to do so
could result in equipment damage.
Fig. 6 — Install Mixing Box
a42-4166
Summary of Contents for AIRSTREAM 42BHE
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