Furnace Repair in Boston, MA
Furnaces here run from October through May. If yours quits, tell us what it's doing and a licensed contractor who covers Suffolk County will get in touch.
Tell us about the job
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Eight months of Boston winter wears a furnace down
Your furnace works from October through May here, eight months of the year. On winter nights averaging 23°F, it is cycling on and off for hours at a stretch to keep the house warm. Every cycle means the igniter fires again, and igniters are built to handle only so many before they fail.
Boston has logged 22 winter storms and 140 damaging wind events over the past ten years, and 10 percent of Massachusetts households lost power for at least 24 hours in 2024 alone. A furnace that shuts down hard when the power drops, then kicks back on once it returns, puts a strain on it that a normal night does not. If yours is slow to relight, or it runs but blows cool air, that is often where the trouble started.
- 8 months
- October through May, your furnace is on duty
- 23°F
- the average winter night it heats against
- 57%
- of homes here heat with gas, so most furnaces here burn gas
- 22 winter storms
- in ten years, the nights a failure hurts most
NOAA nClimDiv, 1991–2020 normals
A new furnace would cut about $200 a year off heating for a typical Suffolk County home.
Estimates for a typical Suffolk County home, compared with an older unit built to the previous federal minimum, from EIA household energy data, Massachusetts fuel prices and NOAA climate normals. Your home will differ.
Repair makes sense when one part has failed and the heat exchanger is sound.
Replacement makes sense when the heat exchanger is cracked or the furnace keeps needing parts.
- Why won't my furnace turn on?
- Start with the thermostat. Check that it's set to heat and the temperature is set above the room temperature, and check the batteries if it has them. If the thermostat looks right, check your breaker panel and any switch near the furnace that looks like a light switch, since that shuts the furnace off for service and is easy to bump. Furnaces built in the last couple decades also won't start if the flame sensor is dirty or the igniter has failed, and those need a contractor to test and replace.
- Why is my furnace blowing cold air?
- Most often the blower is running but the burners haven't lit, so air is moving through the ducts without being heated. A clogged filter can cause this too, since a furnace that overheats will shut its burners off as a safety measure and just keep blowing. Check the filter first. If it's clean and you're still getting cold air, the igniter or flame sensor is likely the problem, and that's a job for a contractor.
- Why won't my furnace pilot light stay lit?
- This usually means the thermocouple is worn out. It's the small sensor that tells the gas valve a flame is present, and once it weakens it shuts the gas off even when the pilot is lit. A draft blowing out the pilot or a dirty pilot orifice can cause the same thing. A contractor can test the thermocouple and replace it, since it's not something to keep relighting on your own.