Furnace Repair in Leesburg, VA
Furnaces here run from October through April. If yours quits, tell us what it's doing and a licensed contractor who covers Loudoun County will get in touch.
Tell us about the job
It takes about a minute.
Seven months of heating, and the cold nights are hardest on it
In Leesburg your furnace runs from October through April. On the coldest nights, when the temperature drops to an average low of 26°F, it cycles on and off for hours at a stretch to keep up. Each cycle means another burner ignition, and that repeated lighting is what wears out an igniter or a flame sensor over a winter.
Most homes here heat with gas, and gas furnaces need electricity to run even though the fuel itself is not affected by an outage. Loudoun County has seen 24 winter storms and 279 damaging wind events over the past ten years, and across Virginia, 22% of households lost power for at least 24 hours in 2024. When the power comes back, most furnaces restart on their own, but not all do.
- 7 months
- October through April, your furnace is on duty
- 26°F
- the average winter night it heats against
- 59%
- of homes here heat with gas, so most furnaces here burn gas
- 24 winter storms
- in ten years, the nights a failure hurts most
NOAA nClimDiv, 1991–2020 normals
A new furnace would cut about $130 a year off heating for a typical Loudoun County home.
Estimates for a typical Loudoun County home, compared with an older unit built to the previous federal minimum, from EIA household energy data, Virginia 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.
Virginia requires HVAC contractors to hold a state license.
The Board for Contractors issues the license, and it covers the contractor rather than any single job. That means the state tested this contractor and keeps a record of them before they ever touch your furnace. Virginia does carve out an exception. Work under $1,000 does not need a licensed contractor, so a small repair can fall outside that requirement.
Gas is the part that makes a furnace repair matter. A loose fitting or a bad connection at the burner is what makes the job dangerous, not the rest of it, and the license is what the state offers as its check on the person making that connection. In Loudoun County, 58.8% of homes heat with gas, and this is the rule that stands behind the contractor working on any of them.
Sources: Virginia General Assembly · Virginia Department of Professional and Occupational Regulation
- Why won't my furnace turn on?
- Start with the thermostat. Make sure it is set to heat and set a few degrees above room temperature, and check that it has power or fresh batteries. If the thermostat looks fine, check the furnace switch, the one that looks like a light switch near the unit, and the breaker for the furnace at the panel. Gas furnaces also need the gas valve open and, on some models, the door panel seated all the way so the safety switch behind it makes contact. If all of that checks out and the furnace still won't start, the ignition system or a safety control is likely the problem, and that calls for a contractor to test it.
- Why is my furnace blowing cold air?
- Most of the time this means the blower is running but the burners haven't lit, or haven't stayed lit. A dirty flame sensor is a common cause. It reads the flame to confirm the gas is burning, and once it's coated enough it shuts the burners off while the fan keeps moving air. A clogged filter can also starve the system and trip a safety limit that cuts the burners but leaves the fan on. If the air has been cold for more than a few minutes, not just the first blast at startup, have a contractor look at the ignition and the flame sensor.
- Why won't my furnace pilot light stay lit?
- This is almost always the thermocouple, the small rod that sits in the pilot flame and tells the gas valve it's safe to stay open. When it wears out or sits slightly out of position, the valve senses no flame and shuts the gas off, even though the pilot was burning a second ago. A draft blowing out the pilot is possible too, but if it happens repeatedly rather than once, the thermocouple is the more likely cause. This is a gas part, so have a contractor replace it rather than trying to adjust it yourself.