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Filters must be used with this furnace. Discuss filter maintenance with the building owner. Filters do not ship with this furnace, but
must be provided, sized and installed externally by the installer. Filters must comply with UL900 or CAN/ULCS111 standards. Damage
or repairs due to the installation of the furnace without filters is not covered under the warranty.
On upflow units, guide dimples locate the side return cutout locations. Use a straight edge to scribe lines connecting the dimples. Cut
out the opening on these lines.
NOTE:
An undersized opening will cause reduced airflow.
Refer to the Filter Sizing Chart to determine filter area requirements.
Filter Sizing Chart
Model
Minimum Recommended Filter Size^
*MSS9*0402BN*
1 - 16 X 25 Side or Bottom
*MSS9*0603BN*
1 - 16 X 25 Side or Bottom
*MSS9*0803BN*
1 - 16 X 25 Side or Bottom
*MSS9*0804CN*
1 - 16 X 25 Side or Bottom
*MSS9*0805CN*
1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*MSS921004CN*
1 - 16 X 25 Side or Bottom
*MSS9*1005CN*
1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*MSS9*1205DN*
1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*CSS9*0402BN*
2 - 10 X 20 or 1 - 16 X 25 Top Return
*CSS9*0603BN*
2 - 10 X 20 or 1 - 16 X 25 Top Return
*CSS9*0804CN*
2 - 10 X 20 or 1 - 16 X 25 Top Return
*CSS9*1005CN*
2 - 14 X 20 or 1 - 20 X 25 Top Return
*CSS961205DN*
2 - 14 X 20 or 1 - 20 X 25 Top Return
^ Other size filters of equal or greater dimensions may be used, filters may
also be centrally located.
Change filters before occupants take ownership of a new home!
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 system than
a standard 1" filter and often has lower static pressure loss than a 1" filter. Also a deep-pleated filter will typically require less
frequent replacement intervals. Avoid using highly restrictive 1" filters which produce static pressure loss greater than .25"
W.C. In some installations the minimum filter size required (consult filter sizing chart above) 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. Consult
your distributor for information on our complete line of IAQ Clean Comfort™ products.