How efficient is the Lennox SLP99V?

The Lennox SLP99V operates at 99% AFUE (Annual Fuel Utilization Efficiency), meaning 99% of the fuel it consumes is converted directly into heat for your home. This is considered a high-efficiency furnace that can qualify for energy rebates.

How much does the Lennox SLP99V cost to install?

The Lennox SLP99V typically costs $7,000 - $9,000 for a complete installation in Nassau County, NY. This includes the furnace unit, professional installation by NATE-certified technicians, permits, and a standard warranty. Actual costs may vary based on your home's specific requirements, ductwork condition, and any necessary modifications.

Is the Lennox SLP99V worth it?

Yes, the Lennox SLP99V is our top pick from Lennox and offers excellent value for its tier. With 99% AFUE efficiency, you can expect to save approximately $230 annually compared to an 80% efficient furnace. Key features like 99% AFUE - highest in industry and Precise Comfort technology make it a compelling choice. It's particularly well-suited for energy-conscious homeowners wanting maximum efficiency.

What is the warranty on the Lennox SLP99V?

Lennox provides parts warranty coverage. For the best warranty protection, we recommend registering your furnace within 60 days of installation. Our installations include a workmanship guarantee on top of the manufacturer warranty.

How long does the Lennox SLP99V last?

With proper maintenance, the Lennox SLP99V should last 15-20 years or more. Premium-tier furnaces like this one often exceed these expectations due to higher-quality components. We recommend annual tune-ups to maximize lifespan and maintain peak efficiency. The extended heat exchanger warranty reflects Lennox's confidence in the unit's durability.

Is the Lennox SLP99V quiet?

The Lennox SLP99V operates at 42 dB, which is very quiet - similar to a refrigerator humming. The modulating operation allows the furnace to run at lower, quieter speeds most of the time.

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Flagship Model

Top Pick

Lennox SLP99V

Model Number: SLP99V

View on Lennox Website

The industrys most efficient gas furnace with Precise Comfort technology and built-in carbon monoxide detection

99% AFUE

Modulating

42 dB

Get Free Quote (516) 345-3911

Technical Specifications

Efficiency (AFUE)99%

Heating StagesModulating

BTU Output Range44k - 110k BTU

Blower MotorVariable-Speed ECM

Sound Rating42 dB

Smart ThermostatStandard

Fuel TypeNatural Gas

Installed Price$7,000 - $9,000

*Prices include equipment, installation, and standard warranty. Actual cost may vary.

Estimated Annual Savings

Compared to an 80% efficient furnace

$230

per year

$3450

over 15 years

Calculate for Your Home

Ideal For

Energy-conscious homeowners wanting maximum efficiency

Expert Review: Lennox SLP99V

The Lennox SLP99V stands alone as the industry's most efficient gas furnace at 99% AFUE, extracting virtually every BTU from the fuel consumed. This flagship model features Precise Comfort technology that modulates both gas input and airflow for incredibly stable temperatures.

In premium Nassau County homes throughout Great Neck and Roslyn, the SLP99V's built-in carbon monoxide detection and SilentComfort technology (operating at just 37 decibels) justify the premium investment. The furnace communicates with the S30 thermostat for truly intelligent home comfort.

At 99% AFUE, this unit qualifies for the maximum PSEG Long Island rebates and federal energy tax credits. Parts are available through Lennox Premier Dealers, though specialized components may require ordering.

The 10-year warranty on all covered components, backed by Lennox's reputation for innovation, provides long-term assurance. The stainless steel secondary heat exchanger resists corrosion from condensate.

Best for: Discerning homeowners who demand the absolute best in efficiency and technology, understanding that premium performance requires premium investment.

Key Features & Technology

99% AFUE - highest in industry

Precise Comfort technology

Carbon monoxide detection

iComfort smart thermostat ready

Warranty & Protection

Parts Warranty

10 Years

Heat Exchanger

Lifetime

Our Guarantee

100% Satisfaction

All warranties require product registration within 60 days of installation. Our team handles registration for you as part of our comprehensive installation service.

Professional Installation

What is Included

Complete furnace unit and materials
Professional NATE-certified installation
Permits and inspections
Old furnace removal and disposal
System testing and calibration
Warranty registration

Installation Timeline

Free Consultation

Same-day or next-day

Installation Day

Typically 4-8 hours

Final Inspection

Ensure perfect operation

Frequently Asked Questions

About Lennox

Lennox

Ranked #2 Overall

Best Efficiency

AFUE Range80-99%

Founded1895

View All Lennox Models

Get Your Free Quote

NATE-certified technicians serving Nassau County with expert Lennox SLP99V installation.

Get Free Quote (516) 345-3911

Available 24/7 for emergencies

Why Home+ Air & Heat?

NATE-certified technicians
Same-day consultations available
Financing options available
100% satisfaction guarantee
Local Nassau County company

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