A furnace not heating requires checking thermostat settings, air filter condition, and gas supply before calling a technician. Start by confirming the thermostat is set to "heat" mode and above room temperature. Inspect the air filter—clogged filters restrict airflow and prevent heat distribution. Verify the gas valve is open and pilot light is lit (for older units). If these steps fail, the issue likely involves a faulty igniter, heat exchanger, or blower motor, requiring professional service.
Why this matters
Missed diagnosis calls cost HVAC contractors $45,000–$120,000 annually in lost revenue. A single diagnostic call at $150–$250 compounds when voicemail abandonment prevents appointment booking. Winter emergencies create call surges; without 24/7 answering, technicians lose jobs to competitors who pick up immediately. Every missed call in heating season is revenue walking to another contractor.
Quick reference
- Thermostat set to "heat" mode is the most common DIY fix
- Replace air filters every 1–3 months depending on usage and pet presence
- Pilot light outages signal igniter or thermocouple failure
- Gas valve must be fully open; a half-closed valve cuts heat output
How it works in practice
A homeowner calls at 6 p.m. on a Sunday complaining of no heat. Your dispatch system with AI voice qualification captures their issue, confirms they've checked the thermostat and filter, and books a Monday 8 a.m. appointment. The AI notes "pilot light won't relight"—your technician arrives prepared with a thermocouple replacement. Answara's 24/7 availability means you capture this call before competitors; custom qualification questions ensure your team knows the problem before arrival.
FAQ
Q: Can a clogged air filter stop heat entirely? A: Yes. A dirty filter blocks airflow, causing the furnace to overheat and shut down on limit switch. Heat won't reach rooms even if the unit runs.
Q: Why does my pilot light keep going out? A: A weak thermocouple, draft, or gas supply issue. Thermocouples cost $25–$50 to replace but require a technician to diagnose safely.
Q: Is a furnace that won't ignite dangerous? A: A furnace that won't ignite safely—the ignition system prevents gas buildup. However, a gas smell requires immediate professional attention and possible evacuation.