Operating instructions

5
5. Locating the Unit - [See Figure 1 and Table 1]
• Locate furnace so fl ue connection to chimney is short,
direct and consists of as few elbows as possible.
• Centralize furnace location with respect to supply and
return air ductwork. Central location minimizes trunk
duct sizing.
• All models may be installed on combustible fl oors.
6. Furnace Used In Conjunction With Air
Conditioning
• Install furnace in parallel with or upstream from
evaporator coil to avoid condensation in heat
exchanger.
• When installed in parallel, prevent chilled air from
entering furnace by use of dampers or air controlling.
• Manually operated dampers must have a control to
prevent operation of either system unless dampers
are in full heat or full cool position.
• Air heated by the furnace shall not pass through
evaporator coil unless coil is specifi cally approved for
such service.
• Check and adjust blower speed to compensate for
pressure drop caused by evaporator coil.
Table 1: Minimum Installation Clearances
Location
Clearance to Combustibles
HML and HMLV
Up fl ow
Top 1" (26 mm)
Bottom 0"
S/A Plenum 1" (26 mm)
Rear 1" (26 mm)
Sides 1" (26 mm)
Front 1"** (26 mm)
Flue Pipe 9"* (229 mm)
Enclosure Closet
*18 in. (458 mm) USA
** 24 in. (610 mm) Service Clearance
Heat Exchanger Support Screws
• Remove heat exchanger support screws before fi nal
placement of the furnace.
• Preferable if furnace rear panel is inaccessible after
installation.
• Screws must be removed if heat exchanger is to be
removed from the cabinet.
Figure 1 - Heat Exchanger Support Screw Location