Installation Instructions Comfort Bridge Models

31
When the furnace is installed without a cooling coil, it is
recommended that a removable access panel be provided
in the outlet air duct. This opening shall be accessible
when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for visual light
inspection or such that a sampling probe can be inserted
into the airstream. The access panel must be made to
prevent air leaks when the furnace is in operation.
When the furnace is heating, the temperature of the return
air entering the furnace must be between 55°F and 100°F.
fIlters - reaD tHIs sectIon Before InstallIng tHe
return aIr Duct
CUT USING TIN SNIPS
SCRIBE LINES OUTLINING
DUCT FLANGES
Dual flange cut outs
fIgure 38
Filters must be used with this furnace. Discuss lter
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 lters is not covered
under the warranty.
On upow 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.
HorIZontal InstallatIons
Filters must be installed in either the central return register
or in the return air duct work.
BottoM return aIr oPenIng [uPflow MoDels]
The bottom return air opening on upow models utilizes
a “lance and cut” method to remove sheet metal from the
duct opening in the base pan. To remove, simply press
out the lanced sections by hand to expose the metal strips
retaining the sheet metal over the duct opening. Using
tin snips, cut the metal strips and remove the sheet metal
covering the duct opening. In the corners of the opening,
cut the sheet metal along the scribe lines to free the duct
anges. Using the scribe line along the duct ange as a
guide, unfold the duct anges around the perimeter of the
opening using a pair of seamer pliers or seamer tongs.
note: aIrflow area wIll Be reDuceD BY
aPProxIMatelY 18% If Duct flanges are left In
factorY PosItIon. tHIs coulD cause PerforMance
Issues anD noIse Issues.
Digital
Manometer
fIgure 37
When the furnace is used in connection with a cooling unit,
the furnace should be installed in parallel with or on the
upstream side of the cooling unit to avoid condensa tion
in the heating element. With a parallel ow arrange ment,
the dampers or other means used to control the ow of
air must be adequate to prevent chilled air from entering
the furnace and, if manually operated, must be equipped
with means to prevent operation of either unit unless the
damper is in the full heat or cool position.
WARNING
eDges of sHeet Metal Holes MaY Be sHarP. use
gloVes as a PrecautIon wHen reMoVIng sHeet
Metal froM return aIr oPenIngs.