Heating and air · checked 5 Oct 2026
The heat isn't working
Safety first
- Gas smell? Leave everyone outside; never touch switches.
- Call 911 and your gas utility from outside.
- Carbon monoxide alarm? Get outside; call 911; stay outside.
Fix it nowEight steps
- Continue only without gas smell, carbon monoxide alarms, or poisoning symptoms.These warnings require evacuation, not troubleshooting.
- Set thermostat to Heat, fan Auto, and temperature above room temperature.The thermostat must request heating.
- Replace thermostat batteries if indicated; follow its manual without touching wires.Dead batteries can prevent a heating request.
The other five steps
- Open supply vents; clear furniture and rugs from return grilles.Blocked airflow can interrupt heating.
- Turn thermostat Off; inspect only a safely reachable, user-accessible filter.Avoid equipment compartments; clogged filters restrict airflow.
- Replace dirty disposable filters with the specified size; follow airflow arrows.Use the manual; never run without a filter.
- Restore Heat; wait several minutes. If heating doesn't resume, call an HVAC technician.Persistent failure needs professional diagnosis.
- Never heat rooms with a gas oven, stove, grill, or indoor generator.These can cause fatal carbon monoxide poisoning.
When to stop
Stop and get a heating and air technician if:
- Gas smell or hissing near gas equipment: leave immediately. Never touch switches, use phones inside, or operate gas valves. Call 911 and your gas utility outside.
- Carbon monoxide alarm: get everyone outside, call 911, and stay out until responders approve reentry.
- Headache, dizziness, or nausea suggesting carbon monoxide exposure: get outside; call poison-control at 1-800-222-1222. If anyone is unconscious or not breathing, call 911 immediately.
- Loud ignition bangs, repeated shutdowns, or a tripped heating breaker: stop troubleshooting and call an HVAC technician. Do not reset repeatedly or relight burners.
- No heat after these checks: call an HVAC technician. Leave gas lines, wiring, and equipment covers alone.
What it probably is
Incorrect thermostat settings or dead batteriesDisplay is blank, mode isn't Heat, or setting is below room temperature.You can check
Clogged filter or blocked ventsFilter is visibly dirty, airflow is weak, or heating stops repeatedly.You can check
Lost electrical powerHeating equipment is silent; other appliances may also lack power.For a pro
Equipment failure or safety shutdownHeat still fails after basic checks, or equipment repeatedly starts and stops.For a pro
Time and parts
- Time
- 10–20 minutes for basic checks
Get it done
More than a quick fix? Vora gets quotes privately and recommends one heating and air technician.
Checked against
- Atmos Energy: Natural Gas Safety Guide
- CPSC: Carbon Monoxide Fact Sheet
- HRSA Poison Help: Carbon Monoxide
- Manufacturer furnace troubleshooting guide
Written for Vora from these public sources and checked on 5 Oct 2026. General guidance, not a substitute for a pro on site. In danger, leave and call 911.