Carbon Monoxide Alarm Going Off

Carbon monoxide is odorless and deadly. A cracked heat exchanger, blocked flue or failed venting can send it into living space. If a CO alarm sounds, treat it as a real emergency—call 911 first, then an HVAC technician to find the source.

Call: 1 (800) 555-0199

Warning signs

A CO alarm sounding
Headaches, dizziness or nausea that improve when you leave the house
Several people or pets feeling sick at once
Soot or yellow flames around a gas appliance

What to do right now

Get everyone—including pets—outside into fresh air immediately
Call 911 from outside
Don't go back inside until responders say it's safe
Have the heating system inspected before using it again

What the HVAC technician will do

After responders clear the home, a technician will inspect the furnace or boiler heat exchanger, flue and venting, and test combustion before the system goes back into service.

What affects the cost

Venting repairs are moderate; a cracked heat exchanger usually means replacing the furnace or boiler. Pricing is set by the independent provider—ask for the trip charge and an estimate before work begins.

Safety first

Carbon monoxide alarm sounding? Get everyone outside and call 911.
Smell gas? Leave now and call your gas utility or 911 from outside. Don't flip switches.
Dangerous heat or cold in your home? Don't wait for a repair—go somewhere safe and check on vulnerable family and neighbors.

Need an emergency HVAC technician?

Call free, 24 hours a day. We'll connect you with an available local provider.