Furnace Installation in Hagerstown, MD
A new furnace here will run from October through April every year. Tell us about the house, and a licensed contractor who covers Washington County will get in touch.
Tell us about the job
It takes about a minute.
What a Hagerstown winter asks of a new furnace
Your furnace here runs from October through April, seven months of the year. Winter nights average 25°F, and on the coldest stretches a new furnace has to cycle on for hours at a time without a break. Whatever gets installed needs to be sized for that cold, not just a mild night here and there.
Washington County has seen 21 winter storms and 148 damaging wind events over the past ten years, and in Maryland, 11 percent of households lost power for 24 hours or more in 2024. Most furnaces need electricity to run the blower and controls even when the heat itself comes from gas, so it is worth asking how yours holds up when the power goes out. A new gas furnace also has to meet the federal minimum of 80 percent AFUE, so ask what efficiency rating you are getting for what you pay.
- 7 months
- October through April, your furnace is on duty
- 25°F
- the average winter night it heats against
- 80% AFUE
- the federal minimum any new unit must meet
NOAA nClimDiv, 1991–2020 normals
Maryland requires HVAC contractors to hold a state license.
The state license is held by the contractor, not issued job by job, so it stays with the business across every furnace they install rather than being renewed or checked each time. Maryland's Board of Heating, Ventilation, Air Conditioning, and Refrigeration Contractors is the body that tests and records who holds it, which means a licensed contractor has met a standard the state set and kept on file.
For a furnace installation in Washington County, the license tells you the contractor has cleared that bar. What checks the work itself is the local building office. Most cities and counties require a permit for a furnace replacement and send someone out to inspect it once it's done, which is where the gas connections and venting get looked at by someone other than the person who installed them.
Sources: Maryland General Assembly · Maryland Department of Labor
- What size furnace does my house need?
- The right size depends on your square footage, your insulation, your windows, and how the house is laid out, so there is no single number that fits every home. A contractor sizes a furnace with a load calculation that looks at all of that together, not just the size of the house. Going too big wastes fuel and wears out the furnace faster by switching on and off too often. Too small, and it will run constantly on the coldest nights and still fall behind. With winter lows here averaging 25°F, getting this number right matters more than it would somewhere milder.
- How do I know it's time to replace my furnace?
- If it is struggling to keep the house warm, cycling on and off more than it used to, or needing repairs more often, those are signs it is wearing out. Age matters too. A furnace working harder each year is one reason to start planning a replacement before it fails outright. Homes here need heat from October through April, seven months of the year, so a furnace that quits in the middle of that stretch is not a small inconvenience. If yours is old and you are already calling for repairs during cold weather, it is worth having a contractor look at whether repair or replacement makes more sense for your situation.
- Is a high-efficiency furnace worth it?
- It depends on how much you heat and what you're comparing it to. Every non-weatherized gas furnace made since November 2015 has to reach at least 80 percent AFUE, so even a standard new furnace is not wasteful by old standards. A high-efficiency furnace goes beyond that minimum, turning more of the fuel it burns into heat for the house rather than losing it. With seven months of heating season here and winter nights averaging 25°F, a furnace here runs more hours over the year than one in a milder climate, which is when the gap between efficiency ratings adds up most. A contractor can walk through the options and what fits your house and your furnace's workload.