7 Furnace Warning Signs to Catch Before a Maryland Winter

The first cold snap of the season is when furnaces that limped through last winter finally quit, and it’s also when every HVAC company in Baltimore County gets busy. Catching problems in the fall usually means a smaller repair, a convenient appointment, and no night without heat.

Here are the seven signs our technicians at Chason Services see most often, and what each one usually means.

1. The furnace turns on and off every few minutes

Called short cycling, this wears out the ignitor, blower motor and controls, and it wastes fuel. Common causes include a clogged air filter that makes the furnace overheat, a dirty flame sensor, a thermostat in a bad spot, or a furnace that’s too big for the house.

What to do: Replace the filter first. If it still cycles quickly, schedule a heater repair visit.

2. New noises: banging, squealing, rattling or grinding

• A bang at startup can mean delayed ignition from dirty burners.
• Squealing often points to a worn blower belt or motor bearings.
• Rattling can be a loose panel, or something more serious inside the cabinet.
• Grinding usually means motor bearings are failing.

What to do: Don’t wait on grinding or loud banging. Small noises get fixed cheaply; ignored ones become a failed motor.

3. A yellow or flickering burner flame

On a gas furnace, a healthy burner flame is mostly steady and blue. A lazy yellow or orange flame can mean incomplete combustion, which produces more carbon monoxide.

4. Some rooms never warm up

Cold bedrooms, a chilly upstairs, or a basement that never feels comfortable can come from a dirty filter, closed or blocked vents, leaky ductwork, or a blower that isn’t moving enough air. In older Maryland homes, it can also mean the duct system was never sized right.

5. Your heating bill jumps without a reason

If your gas or electric bill climbs compared with the same month last year and the weather hasn’t been colder, your furnace is likely working harder for the same heat. Dirty burners, a failing blower, or a system near the end of its life are common culprits.

6. Dust, dry air or a burning smell that won’t go away

A light burning smell for the first few minutes of the season is normal; it’s dust burning off the heat exchanger. A smell that lasts, or a hot electrical or plastic smell, is not. Turn the system off and call a technician.

Very dry air in winter is common in Maryland homes. A whole-home humidifier can help with dry skin, static and cracking woodwork.

7. The furnace is 15 to 20 years old

A well-maintained gas furnace usually lasts about 15 to 20 years. Past that point, repairs come more often and efficiency drops. That doesn’t mean you must replace it, but it’s worth knowing your options before it fails in January.

The easiest fix: a fall tune-up

An annual heating tune-up catches most of these problems early. A technician cleans and checks the burners, flame sensor, ignitor, blower, electrical connections and safety controls, and tells you if anything is wearing out. Between visits, change your filter every 1 to 3 months during heating season.

If your furnace is older and needs a major repair, our furnace page explains repair-versus-replace, and we offer free same-day estimates on new Carrier® heating systems.