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HVAC Technician
Bayport, NY

One-Year Guarantee for New Installs

Free On-Site Estimates for New Equipment

Emergency Services Available

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One-Year Guarantee for New Installs

Free On-Site Estimates for New Equipment

Emergency Services Available

Request Lorem Epsom

Hero Request Form

Four Generations of Heating and Cooling Excellence Since 1937

Donlon Brothers Heating & Cooling Inc has provided dependable heating and air conditioning services to Bayport, NY since 1937. Our family-owned business carries on a legacy that began when oil burners first emerged, and we continue to adapt as technology progresses while maintaining the same commitment to quality service.

As a first-responder-owned and operated and operated company serving Suffolk County, NY, we understand the importance of safety and reliability in every installation and repair. Our fourth-generation team delivers personalized service that larger companies cannot match. Ready to see what a small, dedicated business can do for you? Contact us today.

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Why Choose Us

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One-Year Guarantee for New Installs

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Free On-Site Estimates for New Equipment

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Emergency Services Available

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Service Contracts Available

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Family-Owned & Operated

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Licensed & Fully Insured

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First Responder-Owned & Operated

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Four Generations of Experience

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AC Services

Our air conditioning services throughout Suffolk County include installation, repair, and maintenance of all major brands including Carrier, Rheem & Comfort Air Systems. We provide emergency services when your cooling system fails during the hottest days of summer.

Air Quality Services
We offer comprehensive indoor air quality solutions to keep your home or business healthy and comfortable. Our certified technicians assess and improve ventilation, filtration, and overall air quality throughout your property.
Emergency Heating and Air Repair
HVAC emergencies happen at any time, which is why we provide emergency repair services when you need them most. Our rapid response gets your comfort and safety restored quickly.
Heating Oil Service
With expertise dating back to when oil burners first came to market, we specialize in heating oil systems including Becket and Riello burners. Our knowledge spans generations, providing efficient operation and reliable performance.
Heating Services
From Peerless and Slant/Fin boilers to modern heating systems, we install and service all types of heating equipment. Every new installation includes a one-year guarantee, and we discuss manufacturer warranties with you.
High-Efficiency HVAC
Switch to high-efficiency heating and cooling systems that reduce energy costs while improving comfort. We provide free on-site estimates for new equipment and will consider legitimate bids to give you the best value.
HVAC Testing

We provide comprehensive HVAC testing and diagnostics to help keep your system running safely and efficiently. Our detailed evaluations allow us to accurately identify performance issues and optimize your equipment's operation.

Seasonal HVAC Maintenance
Regular seasonal maintenance prevents breakdowns and extends equipment life. Ask about our service contract discounts that make preventive care more affordable while giving you priority scheduling.
Specialty HVAC Services

We handle specialized systems including System 2000 controls and specialize in oil fired equipment that require advanced technical knowledge. Our licensed and fully insured team brings decades of hands-on experience to every unique challenge.

Water Heater Repair
When your water heater fails, our technicians quickly diagnose and repair the issue to restore hot water to your property. We work on all major brands and models with efficient, reliable service.

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Our Recent Heating Services

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Here's what our satisfied customers are saying...

At Donlon Brothers Heating & Cooling Inc, we take pride in providing exceptional HVAC services to our customers. We would be grateful if you could share your thoughts about our HVAC company with others. Your feedback helps us improve and helps others make informed decisions. Please take a moment to leave a review of Donlon Brothers and let others know what you think.