Furnace Installation & Replacement

When your home's heat source is on the line, you deserve an installation done right — the first time.

A furnace is not something most homeowners think about until it stops working. But when it does — especially in the middle of a Massachusetts winter — the decision you make next matters. At Shelly Heating and Cooling, we approach every furnace installation and replacement the same way: figure out exactly what your home needs, recommend the right equipment, and install it correctly. We are not trying to sell you the most expensive unit on the shelf. We are trying to make sure your home stays warm reliably for the next 15 to 20 years.

Every home is different. The size of your space, the layout of your ductwork, the age of your existing system — all of it factors into which furnace makes sense for you. We handle the full job from equipment selection through final testing. Whether you are replacing a failed unit on an emergency basis or planning a proactive upgrade before winter hits, we work through the entire process with you. Homeowners across Winchendon, Gardner, Athol, Fitchburg, and the surrounding towns in Worcester County cout on us for this work because we show up prepared and do not cut corners.

When the installation is done, you will feel the difference. A properly sized and installed furnace heats your home evenly, runs quietly, and does not spike your energy bill. We walk you through everything before we leave — how the system operates, what to watch for, and how to keep it running well. If you are ready to stop dealing with an unreliable heating system, call Shelly Heating and Cooling at (978) 868-3403. We are available around the clock and ready to help.

What We Offer:

Full Furnace Replacement — We remove your old unit and install a new furnace completely, including all connections to your existing ductwork and thermostat.
New Construction Furnace Installation — We size and install furnace systems in new homes and additions, making sure equipment matches the heating load of the space.
High-Efficiency Furnace Upgrades — If your current furnace is aging and driving up your heating costs, we install high-efficiency models that reduce energy use without sacrificing comfort.
Gas & Propane Furnace Installation — We work with both gas and propane systems, which are common across Winchendon, Templeton, Ashburnham, and surrounding rural communities.
Emergency Replacement Service — When a furnace fails with no warning, we are available 24 hours a day to assess the situation and get a replacement installed as quickly as possible.
Thermostat Integration — Every installation includes proper thermostat hookup and configuration, including smart thermostat compatibility if you want better control over your system.
Post-Installation System Testing — Before we leave, we run the full system through a complete test cycle to confirm everything is operating safely and efficiently.

Why Choose Shelly Heating and Cooling for Furnace Installation & Replacement

Proper Equipment Sizing — An oversized or undersized furnace causes problems from day one. We calculate the correct size for your specific home before recommending any equipment, so you are not paying for capacity you do not need or struggling with a unit that cannot keep up.
Available When You Need It Most — Furnaces do not always fail at convenient times. We are available 24 hours a day, 7 days a week across Winchendon and the surrounding area. If your heating system gives out overnight or on a weekend, we answer the call.
Local Family-Owned Business — Shawn and Julia Shelly run this operation themselves. Every job they take on reflects directly on their name and their reputation in this community. You are not working with a large company that sends out whoever is available — you are working with the people who actually own the business.
Honest Recommendations — If your existing furnace can be repaired at a reasonable cost, we will tell you that. We only recommend full replacement when it genuinely makes financial and practical sense. You get a straight answer, not a sales pitch.
Serving Central Massachusetts and Southern NH — We know the homes in this region, the climate demands they face, and the types of systems commonly installed here. That local knowledge speeds up every job and means fewer surprises once the work is underway.