Reznor CAUA Option - Installation - Mixing Box Installation - Manual

Form I-CAUA-MB, P/N170640R2, Page 1
Form I-CAUA-MB (Version B)
Obsoletes I-CAUA-MB (Version A)
Installation Instructions
Applies to: Optional Outside Air/Return Air
Mixing Box with Dampers
on Model CAUA
Description/
Application
The optional mixing box for the Model CAUA heater is designed to provide the system
with a supply air mixture of return air and outside air. ( NOTE: Application with a mixed
air temperature below 35°F (2°C) requires that the CAUA unit be ordered with Option
AD4.) The mixing box is available in an assortment of configurations with a selection
of actuators and controls for both heating and cooling mode (for units equipped with
a cooling coil). The mixing box is completely assembled at the factory for field attach-
ment to the rear of a Model CAUA heater. It is recommended that the furnace be in its
final location before attaching the mixing box.
All mixing box inlet air openings have duct flanges for attachment of ductwork. Remov-
able door panels provide for filter access from either end of the cabinet. If the box was
ordered with filters (Option AW9 or AW11), it is shipped with the filters installed. (For
replacement filter sizes, see page 4.)
Airflow
Configurations
The optional mixing box
is available in a variety
of configurations to
match the installation.
The mixing box attaches
to the rear of the heater
and provides one of the
airflow configurations
described by option code
(GA1-9) in the table on
the right.
Option
Code
Opening for Outside Air Opening for Return Air
Location on
Mixing Box
Includes
Dampers
Location on
Mixing Box
Includes
Dampers
GA1 Top Yes Bottom or Rear No
GA2 Rear Yes Top or Bottom No
GA3 Bottom Yes Top or Rear No
GA4 Bottom Yes Rear Yes
GA5 Bottom Yes Top Yes
GA6 Rear Yes Top Yes
GA7 Rear Yes Bottom Yes
GA8 Top Yes Rear Yes
GA9 Top Yes Bottom Yes
Mixing Box Dimensions
FIGURE 1 - Mixing Box Dimensions
Inlet Opening with Duct Flange
(if bottom inlet, opening is
symmetrical with top view)
Airflow
19-1/2” (495mm)
2” (51mm)
19-1/2” (495mm)
3-3/8” (86mm)
C
A
B C
Rear View
Inlet Opening with Duct Flange -
Dimensions A, B, and C
apply to rear, bottom, or top inlet.
Top View
End View
(Removable Filter
Access Door -
on both ends)
Airflow
30-1/8”
(765mm)
3/8” (10mm)
typical
26-1/8” (664mm)
27” (686mm)
This side att
aches to
the rear of the heater
.
Size
150-200 250-400
inches mm inches mm
*A 38 965 50 1270
*B 22 578 36-1/2 927
*C 7-5/8 194 6-3/4 171
*Dimensions apply when inlet is located on top,
bottom, or rear of box.