What to Do If Your Carbon Monoxide Alarm Goes Off in Winter

In the middle of winter in Catskill and the Hudson Valley, your home is sealed tight, and your heating systems are working hard. That is exactly why carbon monoxide (CO) alarms are so important, and why you should take them very seriously if they go off.

Carbon monoxide is:

• Colorless
• Odorless
• Tasteless

It is also potentially deadly when it builds up indoors.

If your CO alarm suddenly starts beeping, it is not the time to search and wait. It is the time to act.

This article explains:

• Exactly what to do the moment the alarm sounds
• When to evacuate, call 911, and shut down appliances
• Why you should not go back to normal until inspections are complete
• How chimney and vent inspections fit into post-CO safety
• How True Ventilation helps Hudson Valley homeowners after a CO incident

Treat every CO alarm activation as real unless professionals prove otherwise. Carbon monoxide is too dangerous to gamble with.

Instruct everyone in the home, including pets, to go outside into fresh air.

• Use doors, not windows, unless absolutely necessary.
• Do not stop to investigate the cause before leaving.

If someone is showing symptoms such as:

• Headache
• Dizziness
• Nausea
• Confusion
• Weakness

get them outside quickly and tell emergency responders about their symptoms.

Once you are safely outside or in fresh air, call 911.

Be prepared to tell them:

• That your CO alarm went off
• Whether anyone has symptoms
• That you have evacuated the building

Follow their instructions closely. If they tell you not to re-enter, do not go back inside.

Only if you can do this without delaying evacuation or putting yourself at risk, you may:

• Turn off the furnace at the thermostat or emergency shutoff
• Turn off gas fireplaces or stoves

Avoid flipping multiple switches or lingering in the home. If you are unsure, or it would take more than a few seconds, skip this step and focus on getting out.

Opening windows and doors can help lower CO levels, but it is not a substitute for leaving the building.

Correct order:

• Evacuate
• Call 911
• Open windows and doors only if you can do so quickly and safely on your way out

You should only go back inside when:

• Emergency responders have checked the home
• They confirm that CO levels are safe
• They give you clear permission to re-enter

Even then, do not simply turn everything back on and carry on as if nothing happened. Something caused the CO event and that cause must be identified and fixed.

After a CO alarm, you should not use any of the following until they have been inspected by qualified professionals:

• Fireplaces (gas or wood)
• Wood stoves
• Gas furnaces or boilers
• Gas water heaters
• Gas dryers

A blocked furnace flue, damaged chimney liner, faulty gas fireplace vent, or clogged dryer vent may have caused the problem.

If you turn these systems back on without fixing the root cause, the CO issue can return, possibly at higher levels.

This is where a chimney and venting specialist, such as True Ventilation is essential.

Once emergency responders have handled the immediate danger, the next step is to find out what went wrong.

Common venting-related causes of CO issues include:

• Blocked chimney flues from nests, debris, creosote, or internal collapse
• Damaged, corroded, or undersized furnace flues
• Broken, loose, or backdrafting gas fireplace vents
• Clogged dryer vents, especially with gas dryers
• Failed or missing chimney caps that allow animals and debris inside
• Hidden liner cracks that let gases leak into walls or living spaces

A post-CO chimney and vent inspection should include:

• Full visual inspection of chimneys, flues, and vents
• Checking for obstructions, collapses, corrosion, or disconnected sections
• Verifying proper draft and airflow
• Confirming venting connections are secure and code-compliant
• Reporting on any damaged or unsafe sections
• Recommendations for repair, relining, or replacement

True Ventilation specializes in this type of diagnostic work for Catskill and Hudson Valley homes.

When you call True Ventilation after a carbon monoxide alarm, we follow a clear process to help restore safety and peace of mind.

1. Start with Questions and History

• Which appliances were running when the alarm went off
• Whether anyone experienced symptoms
• What emergency responders found or recommended

2. Inspect All Relevant Venting Systems

Depending on your home, this can include:

• Fireplace and chimney flues for wood and gas systems
• Furnace and boiler flues
• Gas fireplace vents (direct-vent or B-vent)
• Dryer vents, especially for gas dryers

3. Identify the Likely Source or Sources

We look for:

• Blockages from nests, debris, creosote, lint, or structural damage
• Failed components such as caps, liners, or vent joints
• Poor design or installation issues that may cause backdrafts

4. Provide Clear, Actionable Recommendations

We explain:

• What we found, often with photos for clarity
• What must be fixed before you use the affected appliance again
• What is optional but recommended for long-term safety and performance

5. Perform Repairs or Cleaning as Needed

Our services may include:

• Chimney sweeping
• Furnace flue cleaning and repair
• Gas fireplace vent repair and inspection
• Dryer vent cleaning, rerouting, or repair
• Chimney cap, liner, and top-sealing damper installation

• Install carbon monoxide detectors on every level of your home, especially near bedrooms.
• Test CO and smoke alarms monthly and replace batteries regularly.
• Have your chimney, furnace flue, gas fireplace, and dryer vent inspected at least once a year.
• Keep exterior vents clear of snow, ice, leaves, bird nests, and other obstructions.
• Never block air vents or fresh air supplies to heating appliances.
• Never ignore symptoms such as headaches or dizziness when your heating system is running.
• Call a professional if your CO alarm activates, even if it stops on its own.

True Ventilation proudly helps families across:

• Catskill
• Hudson
• Saugerties
• Kingston
• Woodstock
• And surrounding Hudson Valley communities

We focus on chimney and vent safety, including post-CO-event inspections, repairs, and preventive maintenance.

A carbon monoxide alarm going off in winter is frightening, but it is also a lifesaving warning. What you do next matters.

Evacuate. Call 911. Do not reuse heating appliances until they have been inspected. Then let professionals, including True Ventilation, help you understand why it happened and what needs to change to keep your home safe.

Fast action and proper inspections add up to a safer, warmer winter in Catskill and the Hudson Valley.