Furnace Repair
A furnace that won't hold heat, won't stay lit, or is cycling strangely is one of the more urgent calls a homeowner makes. HVAC Service Line connects you with independent companies that take furnace repair calls, including emergency service in many areas.
Signs it's time to reach out
- The furnace blows cold or lukewarm air instead of heat
- The pilot light or ignitor won't stay lit
- Short cycling — the furnace turns on and off repeatedly
- Unusual smells, including a burning dust smell on first use of the season or a gas odor
- Banging, rattling, or screeching sounds during startup or operation
- The thermostat isn't communicating with the furnace
- A yellow or flickering pilot flame instead of steady blue
When homeowners typically call
- There's a smell of gas — this warrants immediate attention; leave the home and contact your gas utility or 911 before calling anyone else
- The furnace won't produce heat at all
- The system is cycling on and off more frequently than normal
- You're hearing new or worsening mechanical noises
What a company may inspect
This varies by company, but a visit for furnace repair often includes a look at:
Ignitor, pilot assembly, or heat exchanger condition
Gas pressure and burner operation
Blower motor, belts, and airflow
Thermostat wiring and control board function
Flue and venting for proper exhaust
Air filter and return airflow
Questions worth asking
- Based on what I'm describing, what's the most likely cause?
- Is this something that needs to be addressed the same day?
- Is the heat exchanger involved, and if so, what does that mean for safety?
- What would keep this from happening again next season?
Furnace Repair FAQ
My furnace smells like gas — what should I do? +
If you smell gas, leave the home immediately, avoid switches or open flames, and contact your gas utility or emergency services from outside before calling an HVAC company. This is a safety situation, not a routine repair call.
Why does my furnace keep turning on and off? +
Short cycling has a few common causes: a dirty air filter restricting airflow, a failing thermostat, an oversized furnace for the home, or a flame sensor that needs cleaning. A technician can usually identify the cause with a hands-on inspection.
Is a burning smell from my furnace normal? +
A faint dusty smell the first time you run the furnace each season is common, as dust burns off the heat exchanger, and it should fade within an hour or so. A persistent or strong burning smell is not normal and is worth having checked promptly.
Related services
Furnace Installation & Replacement
Replacing an aging furnace, or installing a new heating system? Talk through sizing and options with a local company.
Learn moreHeating Maintenance
A pre-season furnace tune-up helps catch small problems before the coldest weeks of the year.
Learn moreEmergency HVAC Service
No heat in freezing weather, or no AC in a heat wave? Get connected with a company that takes urgent HVAC calls.
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