Lennox G51MP SERIES Installation Instructions Manual page 14

Horizontal Applications
The G51MP furnace can be installed in horizontal applica-
tions with either right− or left−hand air discharge.
Horizontal Application
Installation Clearances
Right−Hand Discharge
Left End
Bottom (Floor)**
Left−Hand Discharge
Left End
Bottom (Floor)**
Top
Front*
Back
Ends
Vent
Floor
*Front clearance in alcove installation must be 24 in. (610 mm).
Maintain a minimum of 24 in. (610 mm) for front service access.
**A 5−1/2 service clearance must be maintained below the unit to
provide for servicing of the condensate trap.
‡For installations on a combustible floor, do not install the furnace
directly on carpeting, tile or other combustible materials other
than wood flooring.
FIGURE 17
The G51MP may also be installed as a unit heater. Either
suspend the furnace as shown in figure 18, or install the
furnace on a field−fabricated raised platform. The unit
must be supported at both ends and beneath the blower
deck to prevent sagging.
Refer to figure 17 for clearances in horizontal applications.
Top
Right End
Top
Right End
0
0
0
0
0
0‡
Suspended Installation of Horizontal Unit
NOTE − If unit is suspended, horizontal support kit (Cat No.
56J18 ordered separately) or equivalent is recommended
to ensure proper unit support and coil drainage.
1 − Select location for unit keeping in mind service and
other necessary clearances. See figure 17.
2 − Provide service platform in front of unit.
3 − If unit is installed above finished space, fabricate a
drain pan fitted with a 1/2 inch or 3/4 inch N.P.T. fitting.
4 − Using 3/8 inch rods and support frame kit (ordered
separately), fabricate suspension hangers for unit
keeping in mind front service access clearances.
5 − Mount unit on support frame as shown in figure 18.
6 − Continue with exhaust, condensate and intake line
piping instructions.
BLOWER ACCESS PANEL
INTAKE/EXHAUST
CONNECTION
SUPPORT FRAME
7 − If unit is suspended above finished space, hang the
field−provided drain pan below the support frame as
shown in figure 18. Leave 5−1/2 inches for service
clearance below unit for condensate trap.
8 − Route auxiliary drain line so that water draining from
this outlet will be easily noticed by the homeowner. If
necessary, run the condensate line into a condensate
pump to meet drain line slope requirements. The
pump must be rated for use with condensing furnaces.
Protect the condensate discharge line from the pump
to the outside to avoid freezing.
Platform Installation of Horizontal Unit
1 − Select location for unit keeping in mind service and
other necessary clearances. See figure 17.
2 − Construct a raised wooden frame and cover frame
with a plywood sheet. Provide a service platform in
front of unit. If unit is installed above finished space,
fabricate a drain pan to be installed under unit.
When installing the unit in a crawl space, a proper sup-
port platform may be created using cement blocks and
the horizontal support frame kit (ordered separately,
Page 14
3/8 in. RODS
DRAIN PAN
(to protect finished space)
FIGURE 18