Page 4
Requirements
WARNING
Product contains fiberglass wool.
Disturbing the insulation in this product during
installation, maintenance, or repair will expose you
to fiberglass wool dust. Breathing this may cause
lung cancer. (Fiberglass wool is known to the State
of California to cause cancer.)
Fiberglass wool may also cause respiratory, skin,
and eye irritation.
To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact your
supervisor.
Lennox Industries Inc.
P.O. Box 799900
Dallas, TX 75379−9900
Installation of Lennox oil−fired furnaces must conform with
the National Fire Protection Association Standard for the
Installation of Oil Burning Equipment, NFPA No. 31, the
National Electrical Code, ANSI/NFPA No.70 (in the
U.S.A.), CSA Standard CAN/CSA−B139 (in Canada),
Installation Code for Oil Burning Equipment, the Canadian
Electrical Code Part1, CSA 22.1 (Canada), the recommen-
dations of the National Environmental Systems Contrac-
tors Association and any state or provincial laws or local or-
dinances. Authorities having jurisdiction should be
consulted before installation. Such applicable regulations
or requirements take precedence over general instructions
in this manual.
Chimneys and chimney connectors must be of the type and
construction outlined in section 160 of NFPA No. 31.
Air for combustion and ventilation must conform to stan-
dards outlined in section 140 of NFPA No. 31 or, in Canada,
CSA Standard B139. When installing OF23 units in con-
fined spaces such as utility rooms, two combustion air
openings are required. Dimensions of combustion air
openings are shown in table 1. One opening shall be below
burner level and the other opening shall be no more than 6"
(152 mm) from the room’s ceiling.
The combustion air opening should provide a minimum free
area one-half square inch per 1,000 Btu per hour input. This
combustion air should be brought into the area containing the
furnace below the level of the furnace burner.
IMPORTANT
An opening to the outside for combustion air is
strongly recommended, especially in new homes.
Refer to table 1 or the unit plate for specific combus-
tion air opening dimensions.
Table 1
Combustion Air Opening Dimensions
Model No.
Combustion Air Opening
Dimensions (2 required)
O23−105/120
O23−105R/120R
10" X 20" (254 mm X 508 mm)
O23−140/154
O23−140R/154R
11" X 22" (279 mm X 559 mm)
O23−175R/210R
O23−175R/210R
20" X 40" (508 mm X 1016 mm)
This unit is approved for use on combustible flooring and for
clearances to combustible material as listed on unit rating
plate and in table 2. Unit service and accessibility clearances
take precedence over fire protection clearances.
Table 2
Installation Clearances
Clearances
All Unit Sizes
inches (mm)
top of plenum and duct
2 (51)
plenum sides
3 (76)
sides*
6 (152)
rear
24 (610)
front
4 (102)
flue pipe measured vertical**
(measured from above)
9 (229)
NOTE−Service access clearance must be maintained.
*Clearance to allow inspection of furnace and flue connector
shall be provided. 24" (610 mm) at rear and on one side of furnace should
be allowed for cleaning and service of the blower.
**Minimum clearance shown for flue pipe may be reduced by using special
protection as provided by local building codes and the National Fire
Protection Association Standards and CSA 189.
NOTE − When service clearances are greater than fire
protection clearances, service clearances take prece-
dence.
Unit must be adjusted to obtain a temperature rise within
the range listed in table 3 in the Start-Up section of this
manual.
When installed, furnace must be electrically grounded in
accordance with local codes or, in the absence of local
codes, with the current National Electric Code, ANSI/NFPA
No. 70, or Canadian Electric Code (CEC) if an external
electrical source is utilized.
Field wiring connection with unit must meet or exceed
specifications of type T wire and withstand a 63
_
F (17
_
C)
temperature rise.
