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Save up to $4,275 with a New Heating and Cooling System

Now through March 17th

Emergency HVAC Service

Don’t suffer with a broken HVAC system. When you need help, and you need it fast, you can rely on T. F. O’Brien to be there as soon as possible. Call us when you have an emergency, 24/7, even Holidays or weekends.

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HVAC Maintenance & Tune-Ups

Annual maintenance and seasonal tune-ups for your heating or air conditioning system are easy ways to keep your system in great shape and help to maintain the warranty. Plus, with a maintenance agreement with us, you’ll receive top-notch service.

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Conditioning Systems

When the Long Island summers become too hot, make sure your AC system is working. Whether it's AC repair or installation of a new system  we can help keep your Nassau or Suffolk home cool.

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When the cold strikes Long Island, you may find it to be time to upgrade your heating system or repair your existing system. Get long-lasting durability and high-efficiency while saving both energy and money on your utility bills

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We go above and beyond on every project.
It's our promise to you.Learn More

Financing Available

If you’re looking to upgrade your system, but you have to work within a budget, then let T. F. O’Brien help make things a little easier with our financing options.

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12-Year Warranty

When you choose T.F. O'Brien as your heating and air conditioning contractor, you’re also choosing innovative Daikin products that come with an incredible warranty.

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We service all brands including:

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Outstanding job on installation. Attention to detail and genuine care about the job!! 🙂 Thank you.

M.W. - Huntington, NY

Proud to Provide Heating & Air
Conditioning for Long Island Since 1934