If a carbon-monoxide alarm sounds, anyone has possible carbon-monoxide symptoms, you smell gas, see smoke or fire, or suspect a fuel leak, leave the building and contact emergency services or the appropriate utility from outside. For a no-heat call without an immediate hazard, check the thermostat setting and batteries, electrical disconnects and breakers, a visibly blocked air filter, fuel supply, utility outage status, and any displayed fault code—but do not bypass safety controls, repeatedly reset equipment, open sealed panels, or attempt fuel, gas, electrical, or combustion repairs. Protect vulnerable occupants and plumbing, then call an appropriately credentialed HVAC provider with the equipment and failure details.
KEY TAKEAWAYS
What to remember
- Treat gas odor, smoke, fire, a carbon-monoxide alarm, or possible carbon-monoxide symptoms as an emergency—not an HVAC troubleshooting exercise.
- Never heat the home with an oven, grill, generator, or unapproved fuel-burning device.
- Limit homeowner checks to safe, visible controls and record fault codes without defeating equipment safeguards.
- Confirm after-hours eligibility, diagnostic and overtime charges, arrival expectations, and temporary-heat options before authorizing service.
Separate immediate danger from loss of comfort
Leave the building if a carbon-monoxide alarm sounds, occupants develop headache, dizziness, weakness, nausea, confusion, or unusual sleepiness, you smell gas or another fuel, or there is smoke, fire, sparking, flooding around equipment, or a suspected exhaust problem. Call 911 or the appropriate utility emergency line from a safe location. Do not re-enter or restart equipment until responders say it is safe.
Avoid dangerous substitute heat
Connecticut DPH identifies generators, fuel-burning portable heaters, furnaces, grills, and vehicle exhaust as common carbon-monoxide sources. Never use an oven or grill to heat the home, and never run a generator in a home, basement, garage, porch, or near openings. Follow CPSC placement guidance, keep exhaust directed away, and maintain working smoke and carbon-monoxide alarms with battery backup.
Make only basic, non-invasive checks
If no immediate hazard exists, confirm that the thermostat is set to heat, the temperature setting is above room temperature, and replace thermostat batteries if the display is weak or blank. Check an accessible service switch and electrical panel once, look for a clearly clogged filter, confirm that fuel has not run out, check the utility's outage channel, and photograph any error code. Stop if a breaker trips again, equipment locks out, you see water or soot, or the safe next step is unclear.
Protect people and plumbing while waiting
Move infants, older adults, people with medical conditions, and anyone unable to stay safely warm to a heated location early. Close doors to unused rooms, use safe layers and blankets, and follow public-safety guidance for approved space heaters. During extended cold, know the main water shutoff, open sink-cabinet doors where plumbing runs along exterior walls, and follow official winter-weather guidance to reduce frozen-pipe risk.
Prepare a useful emergency-service call
Provide the service address, safe callback number, equipment type and fuel, brand and model if visible without opening panels, thermostat behavior, fault code, when heat stopped, sounds or odors, prior resets, recent work, fuel status, affected zones, and whether occupants or pipes are at elevated risk. Ask whether the provider serves the address after hours, who qualifies, the diagnostic and overtime charges, expected arrival window, and whether temporary heat is available.
Authorize diagnosis before an open-ended repair
Ask the technician to identify the failed component, likely cause, safety finding, immediate repair, temporary option, price, warranty, and whether additional work is recommended. For a major repair, compare the equipment's condition, remaining service life, recurring failures, code or venting issues, and replacement alternatives. Do not let cold-weather urgency erase written authorization and payment clarity.
Close out the incident
After heat is restored, confirm normal thermostat response, airflow or circulation, combustion and venting checks where relevant, condensate or water-leak checks, carbon-monoxide readings when applicable, fault-code clearance, and any follow-up work. Keep the invoice, diagnosis, parts and labor warranties, settings, service-plan terms, and instructions for safely responding if the fault returns.
HOMEOWNER FAQS
Frequently asked questions
Should I keep resetting a furnace or boiler that will not stay on?
No. One basic control or breaker check may reveal an obvious interruption, but repeated resets can conceal a fault or create risk. Record the code or behavior, stop resetting, and call a qualified provider.
Can I use my gas oven to warm the house?
No. Connecticut DPH warns against using an oven for home heating. It can create fire, burn, and carbon-monoxide hazards.
Does 24/7 service guarantee a technician will arrive immediately?
No. It may mean telephone answering, dispatch for enrolled customers, or technician availability subject to location, weather, workload, and plan terms. Confirm eligibility, charges, and the expected response directly.
What should I do if a carbon-monoxide alarm sounds?
Move everyone outside to fresh air and call 911 from a safe location. Do not search for the source, silence the alarm and remain inside, or restart heating equipment until responders say the property is safe.
How can I reduce frozen-pipe risk during a prolonged outage?
Use official winter-weather guidance, keep vulnerable plumbing exposed to warmer indoor air, know the main shutoff, and consider moving to a heated location before conditions become unsafe. A plumber or local emergency authority can advise on draining or protecting a specific property.
PRIMARY REFERENCES
Sources and further reading
HVACentric uses independent government and standards-based references to support general homeowner guidance. Equipment-specific instructions should always come from the manufacturer.
HVACentric provides general educational information, not a diagnosis for a specific building. Safety, code, equipment, and warranty requirements vary. Use qualified local professionals and verify important decisions directly.