Why does my furnace keep turning on and off?

Short cycling is often a dirty flame sensor, restricted airflow from a clogged filter, or an overheating limit switch. It's inefficient and wears parts fast, so don't ignore it — a contractor can usually resolve it in one visit.

Is a cracked heat exchanger dangerous?

Yes — a cracked heat exchanger can allow carbon monoxide into your home's airflow. Warning signs include soot around the furnace, a flickering burner flame, or headaches and nausea when the heat runs. This is a replace-the-furnace situation and a safety priority: call immediately.

How often should I replace my furnace filter?

Check monthly during heating season; most 1-inch filters need replacement every 1–3 months. A clogged filter is the #1 cause of airflow-related furnace failures and frozen AC coils alike.

My furnace is 18 years old and needs a repair. Should I fix it or replace it?

Furnaces typically last 15–20 years. At 18 with a major failure — especially a heat exchanger or control board — replacement usually makes more sense than another repair. Ask the contractor to assess both paths honestly during the visit.

Do heating contractors offer free estimates?

Many independent contractors in our network offer free estimates. Confirm when you call so you know exactly what to expect from the visit.

No Heat? Get Your Furnace Fixed Fast.

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Direct Answer & Summary

What is Furnace & Heating Repair?

Furnace repair covers gas and electric heating failures: no-heat outages, failed hot-surface igniters, dirty flame sensors, tripped limit switches, blower motor faults, and short cycling. Because heating failures in cold weather can become safety issues, describe your symptoms when you call — no heat in freezing temperatures is prioritized. The contractor diagnoses on site and explains options before any work begins.

Key Points Summary:

Independent local contractors for gas and electric furnaces
No-heat diagnosis: igniters, flame sensors, limit switches, boards
Blower motor and inducer troubleshooting
Carbon monoxide safety checks during heating visits

How It Works

Call with your symptoms

No heat, strange smells, loud startup bangs, or constant cycling — tell us what's happening.

Local contractor diagnosis

The contractor tests ignition, sensors, airflow, and electrical controls to isolate the fault.

Approve the repair

You get a plain-English explanation and your options. No work without your approval.

Does this sound familiar?

Signs You Need Furnace & Heating Repair

Furnace won't turn on
Blowing cold or lukewarm air
Constant on-off short cycling
Loud bang when the furnace starts
Burner flame flickering yellow instead of blue
Soot marks around the furnace
Thermostat calls for heat but nothing happens
Rising heating bills with no change in use

Repair or replace? What contractors look at

Topic	Usually worth repairing	Replacement often makes more sense
System age	Under 12 years old	15–20+ years old
Failure type	Igniter, flame sensor, thermostat	Cracked heat exchanger, failed board
Safety	No CO or gas concerns	Any heat-exchanger or CO issue
History	First breakdown in years	Multiple repairs in recent winters
Efficiency	Heats evenly when running	Rising bills, uneven rooms, constant running