Rheem RGRK-12ERAJS Series Installation Instructions Manual page 14

DOWNFLOW UNITS
1. Position the unit to minimize long
runs of duct or runs of duct with
many turns and elbows.
2. If summer air conditioning is
desired, position the indoor coil
on the supply-air side of the unit.
Insure that no air can bypass this
coil.
3. If installing on a combustible floor
and not using an air
conditioning plenum, install the
special non-combustible floor
base. See Table 1 and Figure 9.
WARNING
THE DOWNFLOW FURNACE
DESIGN IS CERTIFIED FOR
INSTALLATION ON A NON-
COMBUSTIBLE FLOOR. USE THE
SPECIAL BASE SPECIFIED ON
THE FURNACE CLEARANCE
LABEL. FAILURE TO INSTALL THE
SPECIAL BASE MAY RESULT IN
FIRE, PROPERTY DAMAGE,
PERSONAL INJURY OR DEATH.
THIS SPECIAL BASE IS SHIPPED
FROM THE FACTORY AS AN
ACCESSORY.
4. Connect the furnace to the
supply air plenum.
5. Connect the return air ducting to
the return air opening at the top
of the unit. Make the connection
air tight to prevent entraining
combustion gases from an
adjacent fuel-burning appliance.
NOTE: In downflow
configuration, return air cut out is
not permitted.
6. Be sure to have adequate
space for the unit filter.
TABLE 1
NON-COMBUSTIBLE FLOOR BASES
Floor Base
No.
(-)XGC-B17
(-)XGC-B21
(-)XGC-B24
14
NOTE: DO NOT take return air
from bathrooms, kitchens, furnace
rooms, garages, utility or laundry
rooms, or cold areas.
HORIZONTAL UNIT
IMPORTANT: THIS FURNACE MAY
ONLY BE INSTALLED SO AS WHEN
FACING THE FRONT OF THE
FURNACE, SUPPLY AIR IS
DISCHARGED ON THE LEFT HAND
SIDE.
1. Position the unit to minimize long
runs of duct or runs of duct with
many turns and elbows.
2. If summer air conditioning is
desired, position the indoor coil on
the supply air side of the unit.
Insure that no air can bypass this
coil.
3. Connect the furnace to the supply
air plenum.
4. Connect the return air ducting to
the return air opening at the right
end of the unit. Make the
connection air tight to prevent
pulling combustion gases from an
adjacent fuel-burning appliance.
NOTE: In horizontal configuration,
return air cut out is not permitted.
5. Be sure to have adequate space
for the unit filter.
NOTE: DO NOT take return air
from bathrooms, kitchens, furnace
rooms, garages, utility or laundry
rooms, or cold areas.
FIGURE 9
NON-COMBUSTIBLE FLOOR BASE
Size
Cabinet
17
21
24