Looking for furnace installation or replacement in Northern Virginia? Leonard Splaine installs new gas and electric furnaces, right-sized with a real load calculation, quoted free and in writing, with financing options and next-day installation on most equipment.
Why us?
Serving Northern Virginia
A new furnace is only as good as its installation. Before we quote, we run a Manual J load calculation so your furnace is sized to your home, not guessed from the old one. As a Lennox Premier Dealer we install high-efficiency gas and electric furnaces at the AFUE rating that fits your budget, set the venting and gas line to code, seal the duct connections, and haul the old unit away. Replacement quotes cost nothing, financing through our partners includes 0% options, and a no-heat replacement usually goes in the very next day.
Furnace replacements attract high-pressure salesmen; you won't meet one here. Since 1956 this company has sold heat the same way: measure the house, size the equipment to it, and hand over a free written estimate with no theatrics. Being a Lennox Premier Dealer earns you top-tier equipment, and paying by cash or check takes 3% off the total.
Call at any time of night or day and a person, not a phone menu, will set up your free furnace estimate, often for that very afternoon. From estimate to installed furnace, we keep the timeline short and tell you exactly what it is upfront.
Our Services
From the first load calculation to a clean, code-tight install, here's what a new furnace with Leonard Splaine covers.
Ready for a new furnace? We install high-efficiency gas and electric furnaces across Northern Virginia, sized to your home and installed clean: proper venting, a tight gas line, sealed duct connections, and a full start-up and safety check. As a Lennox Premier Dealer we back it with free estimates and next-day installs on most systems.
When it's time to replace, we swap the old furnace out and the new one in, haul away the old equipment, and update the venting and connections to current code. You get an upfront, itemized quote and a system matched to the house instead of whatever was there before.
A higher AFUE rating turns more of your gas into heat and less into waste. We help you find the efficiency sweet spot for a Northern Virginia home and walk you through the payback, plus rebates and 0% financing options, so you upgrade without overpaying for efficiency you won't use.
A new high-efficiency furnace vents differently than an old one, and getting it wrong is a safety issue. We run and pitch the intake and exhaust venting correctly, size it to the equipment, and make sure the combustion air and flue are safe and up to code.
We never size a furnace from the old one's label. We run a Manual J load calculation on your home, factoring square footage, insulation, ductwork, and windows. An oversized furnace short-cycles and wears itself out; an undersized one never keeps up. Right-sizing is the difference between comfort and a callback.
A new furnace is the right time to upgrade the controls. We install and wire smart and programmable thermostats, set up scheduling, and make sure the thermostat and the new furnace communicate properly, so you actually get the efficiency the system is capable of.
Brands
We install and replace new gas and electric furnaces from the best brands. As a Lennox Premier Dealer we match the right furnace to your home and budget, and we service every major brand too.
Current offers
Trust comes first, but fair deals don't hurt. Every furnace installation & replacement offer below is available to every Northern Virginia customer, every day.
Special Offer
On a New Carrier System
0% APR with 60 equal monthly payments on qualifying new Carrier systems, financed through Wells Fargo and subject to credit approval. Sale period August 1 – November 20, 2026. Mention this offer when you book and we'll run the numbers on your replacement.
Expires: 11/20/2026
Special Offer
On a New Lennox System
Rebate up to $1,300, paid as a Lennox Prepaid Mastercard®, on a qualifying Lennox home comfort system, or combine a rebate up to $1,100 with 0% financing for 60 months. Buy July 6 – August 14, 2026; install by August 21. Qualifying system required; see us for details.
Expires: 08/14/2026
Special Offer
Plus 3% Off When You Pay by Cash or Check
Valid ID required. Applies to service visits. Cannot be combined with other discounts or offers. Ask about our 3% discount when paying by cash or check.
Expires: 12/31/2026
The difference
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Reviews
Real reviews from real Leonard Splaine furnace installation & replacement jobs across Northern Virginia. We've earned our 4.9-star average the slow way: answering the phone, showing up on time, and doing right by every home.
Lynn Gilbertson Google review Kyle provided emergency holiday weekend service when our a/c was completely out with 104F "feels like" temperatures. He quickly diagnosed and fixed our system, with solutions for avoiding similar problems in the future. We are grateful to Kyle and Leonard Splaine!
Katie Kada Facebook recommendation Couldn't have asked for better service! Leonard Splaine was timely, honest and did a wonderful job replacing our very outdated AC unit. We plan to use them again for any service or replacement in the future and we'll recommend them to our friends and family.
I will definitely use this company again! Our AC went out on one of the hottest days of the year. They answered and came to the rescue! Family owned and very kind. Technician was knowledgeable and quick.
Ankur Mundra Facebook recommendation I've used Leonard Splaine the last 5 years. They are professional, provide quality service, and answer my questions and concerns. Michael Ford came out this year to do my spring maintenance as well as eztrap installation and condenser coil cleaning. He did an excellent job.
Candace Bond Google review They were such gentlemen and seemed to be very knowledgeable and honest. They were also very patient and took the time to answer all of our questions. I would highly recommend these guys.
A/C stopped working on the hottest day of the year, so far. They came over the same day and had it up and running in no time. The price was reasonable and the tech was great.
Our Team
Every furnace installation & replacement visit is handled by real, named people who treat your home like their own. We're family-owned, 70 years in, and three generations of the same family crew. When you call Leonard Splaine, you reach these folks. Learn more about us.
Ted Leonard 3rd-Generation Owner 
Gary Leonard 2nd-Generation Owner 
Johnny Baker General Manager 
Erin Simmons Office Manager 
Brian Boyce Service Manager 
Brad Hoskins Field Supervisor 
Ira Sacknowitz Install Manager 
Ricky Seminario Comfort Advisor Where we work
Headquartered on Occoquan Road in Woodbridge, we bring furnace installation & replacement to Prince William, Fairfax, Arlington, Alexandria, Stafford, and the towns in between every day.
Don't see your town? If you're in Northern Virginia, call us. Odds are we've got a truck nearby.
Good questions
The questions Northern Virginia homeowners ask us most about furnace installation & replacement. Anything else, the phone's faster than the internet.
It depends on the size, fuel, and efficiency your home needs, which is why we size every furnace with a load calculation instead of a guess. We give you a free, itemized estimate plus 0% financing options so a new furnace fits your budget.
A straightforward furnace replacement is usually a one-day job, and we offer next-day installs on most systems. Jobs that involve new venting, ductwork, or gas-line changes can take longer, and we tell you the timeline upfront.
Higher AFUE means lower gas bills but a higher upfront cost. For most Northern Virginia homes the sweet spot balances the two, and we'll walk you through the payback so you're not overpaying for efficiency you won't use.
With a Manual J load calculation, factoring square footage, insulation, ductwork, and windows. An oversized furnace short-cycles and controls comfort poorly; an undersized one never keeps up. Right-sizing is what makes a new furnace comfortable and efficient.
Yes. We work with several financing partners and pass along manufacturer promotions, including 0% and low-monthly-payment options with approved credit.
Same-day service across Northern Virginia. Talk to a real person, day or night.
