Bryant 987MB, Installation, Start-Up, Operating And Service And Maintenance Instructions

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987MB: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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Connect supply-air duct to flanges on furnace supply-air outlet. Bend
flange upward to 90° with wide duct pliers, see Fig. 19 . The supply-air
duct must be connected to ONLY the furnace supply-outlet-air duct
flanges or air conditioning coil casing (when used). DO NOT cut main
furnace casing side to attach supply air duct, humidifier, or other
accessories. All accessories MUST be connected to duct external to
furnace main casing.
Return Air Connections
The return-air duct may be connected to bottom of the furnace. The side
of casing that faces downward may also be used for return air
connection. A combination of the bottom and downward facing side may
also be used. The upward facing side of the casing cannot be used as a
return air connection, see Fig. 22 .
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. Remove this panel when bottom return air is used.
This panel may be used as a roll-out shield or discard. To remove bottom
closure panel, see Fig. 23 .
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. This panel MUST be in place when side return air
inlet(s) are used without a bottom return air inlet.
Not all horizontal furnaces are approved for side return air connections,
see Fig. 22 . Where required by code, seal bottom closure to furnace with
tape, mastic or other durable sealing method.
Filter Arrangement
Filter and Return Duct Sizing
Pressure drop must be taken into account when sizing filters, filter racks,
IAQ devices, and associated system ductwork. See Table 6 for a
comparison of Pressure Drop (initial/clean resistance to airflow) versus
Airflow for a variety of filter media types and sizes. These are
representative numbers. Consult the filter or IAQ device manufacturers’
specification sheet for performance data for a particular filter media or
IAQ device.
The furnace is shipped with a factory-supplied Media Filter Cabinet. The
Media Filter Cabinet uses either a standard 1-in. (25 mm) filter or 4-in.
(102 mm) wide Media Filter which can be purchased separately. A field
supplied accessory air cleaner may also be used in place of the media
cabinet.
The Media Cabinet is sized for bottom return applications for use in
upflow, downflow and horizontal applications. A 16-inch (406 mm)
Media Cabinet is shipped with the 14-3/16-in. (360 mm) furnace and
includes block-off plates.
For upflow side return applications, the Media Cabinet (or field supplied
accessory air cleaner) can be installed on the side of the furnace or side
and bottom when a bottom plenum is used, see Fig. 20 and Fig. 25 .
For downflow applications, the Media Cabinet (or field supplied
accessory air cleaner) must only be connected to the bottom opening on
the furnace, see Fig. 20 and Fig. 25 .
For horizontal applications, the Media Cabinet (or field supplied
accessory air cleaner) for all models can be connected to the bottom
opening on the furnace. For side return use in the horizontal position,
refer to Fig. 22 . If both side and bottom openings are used in Fig. 22 ,
each opening used will require a filter.
The media cabinet (or field supplied accessory air cleaner) can also be
installed in the common return duct prior to entering the return air
opening in any orientation.
Refer to the instructions supplied with Media Cabinet or accessory air
filter for assembly and other details. See Table 6 for filter size details.
Design the filter and associated ductwork for the best match of pressure
drop versus filter size. Best practice usually chooses filter systems with
pressure drops under 0.2 in. W.C. (50 Pa), with the best blower electrical
efficiency and system airflow performance occurring with filter pressure
drops under 0.1 in. W.C. (25 Pa).
Provide duct transitions, as required, to smoothly transition airflow from
the return duct system to the filter (or IAQ device) to the furnace when
the dimensions of the ductwork or furnace return air opening do not
match the required filter or IAQ device dimensions. See the instructions
supplied with factory-accessory duct adapters.
• Special Base, KGASB
• Cased Coil Assembly Part No. CNPV, CNRV, CAP, or CAR
• Coil Box Part No. KCAKC
Table 6 – Filter Information
WARNING
!
FIRE, CARBON MONOXIDE AND POISONING
HAZARD
Failure to follow this warning could result in fire, personal injury or
death.
Never operate a furnace without a filter or filtration device installed.
Never operate a furnace with filter or filtration device access doors
removed.
FURNACE
CASING
WIDTH
FILTER SIZE
FILTER TYPE SIDE
RETURN
BOTTOM
RETURN
17-1/2 (445)
16 x 25 x 3/4
(406 x 635 x 19)
16 x 25 x 3/4
(406 x 635 x 19)
Washable
*
*. Recommended to maintain air filter face velocity. See Product Data for part
number.
21 (533)
16 x 25 x 3/4
(406 x 635 x 19)
20 x 25 x 3/4
(508 x 635 x 19)
Washable
*
24-1/2 (622)
16 x 25 x 3/4
(406 x 635 x 19)
24 x 25 x 3/4
(610 x 635 x 19)
Washable
*
NOTICE
!
Design the duct system FIRST to determine how much pressure drop
may be allowed in the filter system. See the Air Ducts section.
Excessive filter pressure drop often compromises system airflow and
duct performance, causes inadequate airflow to the furthest ends of the
duct system, as well as causes excess noise and higher than anticipated
electrical consumption.
Filter Media Pressure Drop (Clean) Versus Airflow - In. W.C. (Pa)
14 x 25 Filter
(356 x 635 mm)
Factory-Accessory
Washable
Factory-Accessory
Media*
Representative After-Market Filter Media*
Fiberglass* Pleated*
CFM L/s (1-in. / 2.5 cm) (4-in. / 10 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)
600 (283) 0.04 (12) 0.05 (12) 0.07 (17) 0.10 (26) 0.24 (60) 0.16 (40)
800 (378) 0.06 (15) 0.07 (19) 0.10 (25) 0.15 (39) 0.34 (85) 0.23 (59)
1000 (472) 0.07 (18) 0.10 (27) 0.13 (34) 0.21 (52) - - 0.32 (81)
1200 (566) 0.08 (20) 0.14 (36) 0.17 (43) 0.27 (68) - - - -