sl25kcv
Air Conditioner
The most precise and efficient air conditioner available.
R-454B
All Dave Lennox Signature® Collection models come with a 10-Year Limited Warranty on compressor and covered components. For more information, visit www.Lennox.com/WarrantyYourWay.
Features
INCREASED APPLICATION FLEXIBILITY
The LS25 Separated Combustion Unit Heaters utilize high‑temperature silicone gaskets to provide a superior seal and leakage rates that are up to 57% lower* than those allowed under ANSI Z83.8. Lennox goes above and beyond to deliver a tight, durable seal because that is the key to unmatched durability and efficiency over the life of a separated combustion product in harsh environments. The LS25 design simplifies installation of the unit by not disturbing any of the factory‑installed seals or requiring messy, field‑applied sealants.
BENEFITS OF LS25 SEPARATED COMBUSTION UNITS
INCREASED APPLICATION FLEXIBILITY
• Separated combustion units offer a robust heating solution for buildings with harsh indoor environments.
• Fresh-air intake can be rotated 180˚ degrees on the 125-400 kBtuh models for increased installation flexibility in retrofit applications, which can reduce the number of piping elbows needed to make venting connections.
LOWER OPERATING COSTS
• The separated combustion technology enhances overall energy efficiency of the building by eliminating the continued replacement of conditioned air with unconditioned outside air.
• Up to 5% more efficient than standard efficiency direct-fired unit heaters**
• LS25-250 through LS25-400 kBtuh models lower operating costs by efficiently meeting the demands of the space with two stages of heating.
APPLICATIONS FOR SEPARATED COMBUSTION
Separated combustion LS25 models use outside air for combustion and are designed for use in applications where the indoor environment may contain airborne contaminants, VOC’s and/or dust that would normally be harmful to the combustion process and components.
A refrigerant that’s better for the environment.
This product is compliant with 2025 EPA regulations for lower global warming potential (GWP) refrigerants. The Lennox choice of 2025 Compliant Refrigerant has a lower GWP than its predecessor and is formulated to provide excellent, reliable performance of your system for years to come.
Ratings & Reviews
See what other customers are saying about
SL25KCV Air Conditioner
5/5
New "Top of the line" Lennox system
May 25, 2026This is my 2nd Lennox system in 13 years. Loved the first system. Was still working great until it developed pin hole leaks in the coil. Due to new coolant restrictions, I had to replace the entire system. I purchased the comparable system. So far, it continues to be what I expected from Lennox. It's quiet and efficient. My only complaint is the advertised "up to $1800 rebates", which I got on my last Lennox system, and assumed I would get on this comparable top of the line unit. This system cost me literally twice as much and only gave me a $250 rebate. The $1800 rebate was only offered on the heat pump models, which I wasn't aware of until after installation.
Yes, I recommend this product.
Winter Park, Fl
Age: Over 65`
Gender: Male
Reason for Replacement: Emergency
5/5
3/5
5/5
5/5
Managing my thermostat from afar.
May 22, 2026It is so helpful and comforting to know that I can see and adjust my thermostat settings from 1500 miles away.
3/5
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- * *Efficiency claim based on comparison of the average SEER2 of the SL25KCV as compared to the average SEER2 of the competitive variable capacity compressor units as published in AHRI (September 2024). Actual system efficiency may vary based on the system match and other factors; consult AHRI Directory for exact system efficiency. Precision claim based on the average cooling capacity range of the SL25KCV as compared to the average published cooling capacity of competitive 20 SEER2+ variable capacity compressor units (September 2024). Averages calculated across the full tonnage range available.
