507581-04Page 10  of  60 Issue 2128
Installation
Setting Equipment
Do not connect  the return air ducts to  the back of the 
furnace. Doing so will adversely affect the operation of 
the safety control devices, which could result in personal 
injury or death.
   WARNING
Blower  access  panel  must  be  securely  in  place  when 
blower  and  burners  are  operating.  Gas  fumes,  which 
could  contain  carbon  monoxide,  can  be  drawn  into 
living space resulting in personal injury or death.
   WARNING
Shipping Bolt Removal
Units  with  1/2  hp  blower  motor  are  equipped  with  three 
exible  legs  and  one  rigid  leg. The  rigid  leg  is  equipped 
with a shipping bolt and a at white plastic washer (rather 
than  the  rubber  mounting  grommet  used  with  a  exible 
mounting leg). See Figure 11. The bolt and washer must 
be  removed  before  the  furnace  is  placed  into  operation. 
After the bolt and washer have been removed, the rigid leg 
will not touch the blower housing.
Figure 11. 
Units with 1/2 HP 
Blower Motor
Upow Applications
The gas furnaces can be installed as shipped in the upow 
position. Refer to Figure 13 for clearances. Select a location 
that  allows  for  the  required  clearances  that  are  listed  on 
the unit nameplate. Also consider gas supply connections, 
electrical  supply,  vent  connection,  condensate  trap  and 
drain connections, and installation and service clearances 
[24 inches (610 mm) at unit front]. The unit must be level 
from  side  to  side.  Tilt  the  unit  slightly  (maximum  1/2  in. 
from level) from back to front to aid in the draining of the 
heat exchanger. See Figure 12.
Allow for clearances to combustible materials as indicated 
on the unit nameplate.
Figure 12. Setting Equipment
Tilt the unit slightly (Max. 1/2”) from back to front to aid in the draining of the heat exchanger.
Unit must be level side-to-side in all applications.