Lennox Signature O23V User manual

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O23V Oil Furnace ◆Up to 83% AFUE
Home Comfort Systems
O23V
Variable speed for superior comfort

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Built to exacting standards with the highest-quality components, the
Dave Lennox Signature®Collection O23V oil furnace is a superior way
to keep your home warm and comfortable.
QUIET, EFFICIENT, COMFORTABLE HEATING
Every innovation speaks to quality—from its innovative variable speed
motor to its insulated steel cabinet. For those who refuse to compromise,
the O23V oil furnace is the premium choice, inside and out.
Dave Lennox Signature®Collection O23V Oil Furnace
Innovation never felt so good.
™
EFFICIENCY RATING
Up to 83% AFUE (Annual
Fuel Utilization Efficiency).
WARRANTY*
Limited lifetime warranty
on the heat exchanger.
10-year limited warranty
on all remaining covered
components.
Variable speed operation
assures comfort, efficiency and
considerable noise reduction
Quality components ensure
long-lasting reliability
VARIABLE SPEED MOTOR
*Applies to residential applications only.
See actual warranty certificate for details.
Innovative
Uses variable speed technology
to improve comfort and indoor
air quality
A variable speed motor moves at
different speeds to precisely control
the flow of air throughout your
home. Better airflow control means
a better balance of comfort.
When the variable speed motor
increases speed, it does so smoothly
and gradually. During summer
months, this allows your air
conditioner to remove moisture
from the air for improved comfort
and better indoor air quality.

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Quiet
Exclusive SilentComfort™
technology maximizes your
comfort while minimizing sound
The variable speed motor ramps up
to speed slowly, so there’s no sudden
blast of air at startup. A specially
insulated cabinet further reduces
operating sound.
Healthier
Slowly circulates air for better
indoor air quality
When you set your thermostat to
“FAN,” the O23V continues to
slowly circulate air throughout your
home. That means you can run the
fan constantly without substantially
increasing operating costs.
It also means better indoor air
quality—low-speed fan operation
increases the effectiveness of your
filters, allowing them to capture
and remove more contaminants.
This chart depicts potential energy savings you can
expect from the O23V furnace versus older furnaces with
lower efficiency ratings. Criteria used in this example
are 2,000 full-load heating hours, with a 80,000-Btuh
heating design load and $1.90 per gallon for oil. Your
actual savings will vary depending on the weather, local
fuel rates and your lifestyle.
Source: Energy Information Administration,
U.S. Department of Energy national average energy
rates, 2005 forecast.
AFUE
83 %
vs. 55%
83 %
vs. 65%
$4000
$3500
$3000
$2500
$2000
0
$4033
3-YEAR HEATING SAVINGS
$2194
83% efficient 023V oil furnace vs.
55% and 65% equivalent AFUE units
Efficient
Delivers significant energy
savings all year
The O23V has a heating efficiency
of up to 83% AFUE. Compared to
an older furnace, the O23V can
dramatically reduce your utility bills.
As an added benefit, the O23V’s
variable speed motor uses about
two-thirds less electricity than a
standard motor. During cooling
operation, this typically results in an
efficiency gain of 1 SEER (Seasonal
Energy Efficiency Ratio), which can
add to your energy savings.
VARIABLE SPEED OPERATION
Gradual
Acceleration Humidity
Control
Full Capacity
Gradual
Deceleration
Added
Efficiency
Off
Gradual acceleration and deceleration of the variable speed
motor significantly reduce sound.
Less noise. Less humidity. More comfort.

CONTINUOUS COMFORT NETWORK
The O23V Variable Speed Furnace is designed to easily integrate with other quality Lennox®products, providing
a total home comfort solution:
XC21 Air Conditioner is the most quiet and efficient central air conditioner you can buy.**
PureAir™Air Purification System cleans the air in your home better than any other single system you can buy.
Harmony III™Zoning System provides customized, room-to-room comfort.
**A combination of sound ratings established per ARI’s test standard: 270 and efficiency ratings established per ARI’s test standard: ANSI/ARI 210/240-2005.
O23V Upflow V2/3-70/90 V3/4-105/120 V5-140/154
AFUE 83% 81% 81%
Dimensions HxWxD (in.) 54 x 19-1/2 x 30-5/8 54 x 19-1/2 x 30-5/8 54 x 22-1/2 x 33-1/8
HxWxD (mm) 1372 x 495 x 778 1372 x 495 x 778 1372 x 572 x 841
Note: Due to Lennox’ ongoing commitment to quality, all specifications, ratings and dimensions are subject to change without notice.
Dave Lennox Signature®Collection O23V Specifications
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THIS MODEL
Annual Fuel Utilization Efficiency (AFUE)
Oil-fired forced-air furnace
more energy-efficient 87%
78%
81%-83%
Lennox is proud of the
fact that these products
have earned the Good
Housekeeping Seal.

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INNOVATIVE FEATURES FOR ENHANCED COMFORT AND EFFICIENCY
Heavy-Gauge Steel Heat Exchanger –
Allows air to glide evenly over its smooth surface
for maximum heating efficiency.
Innovative Combustion Chamber –
Constructed from alumina-silica ceramic fiber, provides
quiet operation and high efficiency.
Beckett Burner –
Delivers super-efficient combustion for greater fuel
economy. It’s one of the finest, most trouble-free
burners in the industry.
Heavy-Duty Fuel Pump –
Provides quiet, reliable operation with fast shutoff
of oil flow.
Variable Speed Motor –
Highly efficient motor quietly controls flow of air for
added humidity control, indoor air quality and comfort.
Insulated Blower Compartment –
Minimizes operating sounds.
Durable, Insulated Steel Cabinet –
Built to last and coated with a high-quality paint finish.
O23V
Up to
83% AFUE

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© Lennox Industries Inc. 2005
Visit us at www.lennox.com, or contact us at 1-800-9-LENNOX. PC50736(95M78) O23V 8/07
CUSTOMIZE YOUR COMFORT
Lennox®heating, cooling and Healthy Climate®indoor air quality products are designed to provide efficient, economical
comfort—not only as individual units, but also together as an integrated system. This combined network of products
delivers on every comfort count, from consistent temperatures and balanced humidity to improved indoor air quality.
DEALERS YOU CAN COUNT ON
Choosing the right dealer for your home’s heating, cooling and air quality needs is every bit as important as choosing the
right brand. We think you’ll agree our independent dealers are a big reason you can count on quality customer service
whenever you call. Your Lennox dealer’s dedication to quality shows in his knowledge, training and expertise in designing
the right system for your home, installing it properly and keeping it running perfectly for many years to come.
Air conditioner or heat pump
Thermostat
Furnace or air handler
Filtration device
Germicidal light
Indoor coil
Humidifier
HEPA bypass filtration system
 Energy recovery ventilator
• Supply duct
•• Return duct