Installations Instructions

14
I NSTALLAT ION P OSIT IONS
*MVM97 models may be installed upflow or horizontally with
left or right side down. *CVM97 models may be installed
downflow or horizontally with left or right side down.
Do not install this furnace on its back. For upright upf l ow
furnaces, return air ductwork may be attached to the side
panel(s) and/or basepan. For hor i zont al upf l ow furnaces,
return air ductwork must be attached to the basepan. For
both upright or hor izont al count erf low furnaces, return duct-
work must be attached to the basepan (top end of the blower
compartment). NOTE: Ductwork must never be attached to
the back of the furnace. Refer to “Recommended Installa-
tion Positions” figure for appropriate installation positions,
ductwork connections, and resulting airflow arrangements.
Figure 4A
Figure 4B
Figure 4C
Recommended Installation Positions
H ORIZONTAL A PPLICAT IONS & C ONSIDERAT IONS
When installing a furnace horizontally, additional consider-
ation must be given to the following:
FURNACE SUSPENSION
If suspending the furnace from rafters or joists, use 3/8"
threaded rod and 2”x2”x1/8” angle iron as shown in the fol-
lowing diagram. The length of rod will depend on the applica-
tion and the clearances necessary.
If the furnace is installed in a crawl space it must be sus-
pended from the floor joist or supported by a concrete pad.
Never install the furnace on the ground or allow it to be ex-
posed to water.
2" 2" 3/8" ANGLE IRON
(3 PLACES )
XX
Figure 5
FRONT COVER PRESSURE SWITCH TUBE LOCATION
When a furnace is installed horizontally with left side down,
the front cover pressure switch tube must be re-located
to the lower port of the collector box cover.
1. Remove tube from front cover pressure switch and
collector box cover.
2. Remove rubber plug from bottom collector box port
and install on top collector box port.
3. Locate 24” x 1/4” tube in bag assembly.
4. Install one end on front cover pressure switch.
5. Route tube to lower port on collector box cover and
cut off excess tubing.
DRAIN TRAP AND LINES
In horizontal applications the condensate drain trap is se-
cured to the furnace side panel, suspending it below the fur-
nace. A minimum clearance of 5 1/2 inches below the fur-
nace must be provided for the drain trap. Additionally, the
appropriate downward piping slope must be maintained from
the drain trap to the drain location. Refer to Condensat e Dr ai n
Tr ap and Lines for further details. If the drain trap and drain
line will be exposed to temperatures near or below freezing,
adequate measures must be taken to prevent condensate from
freezing.