Service Manual

INSTALLATION CONSIDERATIONS
40
vent operation of either unit unless the damper is in the full
heat or cool position.
When the furnace is heating, the temperature of the return
air entering the furnace must be between 55°F and 100°F.
Consider installing an air cleaner with deep-pleated media
filter at the time of furnace installation. A deep-pleated filter
with a MERV rating of 8 (minimum) will often provide better
filtration to protect equipment and the air distribution sys-
tem than a standard 1" filter and often has lower static pres-
sure loss than a 1" filter. Also a deep-pleated filter will typi-
cally require less frequent replacement intervals. Avoid us-
ing highly restrictive 1" filters which produce static pressure
loss greater than .25" W.C. In some installations the mini-
mum filter size required (consult filter sizing chart ) will not
lend itself to a filter installation on the side of the furnace.
The installation of a centrally installed air cleaner cabinet or
a return duct filter installation may offer more practicality.
Clean Comfort™ brand MERV 11 air cleaners have 5¼” media
filters and are available in the following configurations. Con-
sult your distributor for information on our complete line of
IAQ Clean Comfort™ products.
UPRIGHT FILTER INSTALLATIONS
Depending on the installation and/or customer preference,
differing filter arrangements can be applied. Filters can
beinstalled in the central return register and a side panel
extern filter rack kit (upflow filter kit # EFR01). As an alter-
native a media air filter or electronic air cleaner can be used
as the requested filter. Refer to the following minimum filter
requirement charts for determination of the minimum filter
area to ensure proper unit performance. The following fig-
ures show possible filter locations. NOTE: A ductwork ac-
cess door must be used in counterflow applications to allow
filter removal.
COUNTERFLOW FILTER INSTALLATION
This furnace has provisions for the installation of return air
filters at the counterflow top return. The furnace will accom-
modate the following filter sizes depending on cabinet size:
Model Minimum Recommended Filter Size^
*MVC960403BN* 1 - 16 X 25 Side or Bottom
*MVC960603BN* 1 - 16 X 25 Side or Bottom
*MVC960803BN* 1 - 16 X 25 Side or Bottom
*MVC960804CN* 1 - 16 X 25 Side or Bottom
*MVC961005CN* 1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*MVC961005DN* 1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*MVC961205DN* 1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*CVC960403BN* 2 - 10 X 20 or 1 - 16 X 25 Top Return
*CVC960603BN* 2 - 10 X 20 or 1 - 16 X 25 Top Return
*CVC960804CN* 2 - 10 X 20 or 1 - 16 X 25 Top Return
*CVC961005CN* 2 - 14 X 20 or 1 - 20 X 25 Top Return
*CVC961205DN* 2 - 14 X 20 or 1 - 20 X 25 Top Return
^
Larger filters may be used, filters may also be centrally located
Upflow furnaces with air delivery of less than 1800 CFM:
Use one side return or one bottom return ductwork connec-
tion.
Upflow furnaces with air delivery of 1800 CFM or higher:
Use two side returns or one side return and one bottom
return connection.
Guide dimples locate the side and bottom return cutout lo-
cations. Use a straight edge to scribe lines connecting the
dimples. Cut out the opening on these lines. An undersized
opening will cause reduced airflow. For bottom return con-
nection, remove the bottom of the cabinet before setting the
furnace on the raised platform or return air duct.
A closed return duct system must be used, with the return
duct connected to the furnace. NOTE: Ductwork must never
be attached to the back of the furnace. Supply and return
connections to the furnace may be made with flexible joints
to reduce noise transmission, if desired. If a central return is
used, a connecting duct must be installed between the unit
and the utility room wall so the blower will not interfere with
combustion air or draft. The room, closet, or alcove must
not be used as a return air chamber.
When the furnace is used in connection with a cooling unit,
the furnace should be installed in parallel with or on the up-
stream side of the cooling unit to avoid condensation in the
heating element. With a parallel flow arrangement, the damp-
ers or other means used to control the flow of air must be
adequate to prevent chilled air from entering the furnace and,
if manually operated, must be equipped with means to pre-