When your heating or cooling system fails, your home's comfort and safety are immediately compromised. A furnace that quits during a frigid Sudbury winter night or an air conditioner that breaks down in the peak of a humid New England summer isn't just an inconvenience—it's an emergency. You need a reliable, local expert who can diagnose the problem accurately and provide a lasting solution, fast. We specialize in comprehensive HVAC repair services for residents and businesses throughout Sudbury, MA, ensuring your system is restored to optimal performance with precision and care.
Our team of certified technicians is equipped to handle the complexities of modern and legacy HVAC systems. We understand the unique demands that our local climate places on heating and air conditioning equipment, and we arrive prepared to address any issue, big or small. From minor fixes to major component replacements, our goal is to get your system back online efficiently, restoring your comfort and peace of mind.
When the summer heat and humidity set in, a functioning air conditioner is essential for a comfortable indoor environment. If your AC system is struggling, you may notice warning signs like weak airflow, strange noises, unpleasant odors, or an inability to reach the set temperature.
Our technicians are proficient in diagnosing and repairing all types of air conditioning systems, including central air units, ductless mini-splits, and heat pumps. Common AC issues we resolve for Sudbury homeowners include:

A reliable heating system is non-negotiable during a Massachusetts winter. A malfunctioning furnace not only affects your comfort but can also pose significant safety risks, such as carbon monoxide leaks. If your furnace is making unusual noises, cycling on and off too frequently, or simply not producing enough heat, it's time to call a professional.
We provide expert repair services for all major types of heating systems, including gas furnaces, oil furnaces, and heat pumps. Our heating repair solutions cover:
Heat pumps are an efficient, all-in-one solution for both heating and cooling, but their dual-function nature means they can experience unique issues. Whether your heat pump is stuck in one mode, blowing cool air in winter, or failing to dehumidify in the summer, our technicians have the specialized knowledge to fix it. We handle everything from reversing valve failures and refrigerant charge issues to defrost control problems, ensuring your system provides year-round comfort as intended.
We believe in a transparent and thorough approach to every service call in Sudbury. When you schedule a repair, you can expect a meticulous process designed to provide a lasting solution, not a temporary patch.
HVAC emergencies don't wait for convenient business hours. A complete system failure in extreme weather requires immediate attention. We offer responsive emergency repair services to address your most urgent heating and cooling needs. Our team is ready to act quickly to protect your home and family from dangerous temperatures, restoring your system's functionality when you need it most.
Don't let a malfunctioning HVAC system disrupt your life. For prompt, professional, and reliable HVAC repair in Sudbury, MA, trust the local experts dedicated to restoring your comfort.
Contact us today to schedule your HVAC repair service and restore comfort to your home.
System acting up? Don’t sweat it—Lavallee Systems provides prompt, effective HVAC repair in Sudbury, MA, resolving breakdowns before they disrupt your home life. Our expert technicians arrive ready to diagnose, fix, and restore comfort fast—no guesswork, just results.
Enjoy discounted pricing on our already affordable maintenance services.
Save on necessary repairs with a fixed discount.
Upgrade your system with an exclusive member discount.
Avoid the $300 fee if emergency service is ever required.
When you need service, you’ll be at the top of our list for the fastest possible response.