Carbon Monoxide and Gas Furnace Safety
Concerned about carbon monoxide from your furnace? Learn the warning signs, how to stay safe, and when to call for emergency service.
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Emergency Warning
This issue may require immediate professional attention. If you're experiencing this problem, especially with any safety concerns, call us immediately.
Call Now: (650) 540-7205Safety Warning
Carbon monoxide is deadly. If your CO detector alarms, leave immediately and call 911. Do not try to find the source yourself.
Understanding the Problem
Carbon monoxide (CO) is an invisible, odorless gas that can be produced by malfunctioning gas furnaces. It's extremely dangerous because you can't detect it without proper equipment. Understanding furnace safety and the warning signs of CO problems could save lives. Every home with a gas furnace should have CO detectors, and the furnace should be professionally inspected annually to check for safety issues including heat exchanger cracks.
Common Symptoms
You might be experiencing this problem if you notice:
- CO detector alarming
- Yellow or orange burner flame (should be blue)
- Soot or burn marks around furnace
- Excessive condensation on windows
- Family members experiencing headaches, nausea, dizziness
- Symptoms improve when leaving the house
Possible Causes
This problem can be caused by several factors, listed from most to least likely:
Cracked heat exchanger
Heat exchanger replacement or furnace replacement. This is a serious safety issue.
Blocked flue or exhaust
Professional inspection and clearing of flue/exhaust system.
Improper combustion
Professional tune-up and combustion analysis.
Malfunctioning CO detector
Check detector age and batteries. Replace if over 5-7 years old. If in doubt, evacuate and call fire department.
DIY Troubleshooting Steps
Before calling a professional, try these safe troubleshooting steps:
- 1
If CO detector alarms: LEAVE THE HOUSE IMMEDIATELY
- 2
Call 911 from outside
- 3
Don't re-enter until cleared by fire department
- 4
Have furnace professionally inspected before using again
- 5
Check CO detectors regularly and replace batteries annually
When to Call a Professional
Contact a licensed HVAC technician if:
- Any CO detector alarm (call fire department first, then HVAC)
- Yellow or flickering burner flames
- Visible soot or damage
- Annual inspection is overdue
- Family members experiencing symptoms
Prevention Tips
Help prevent this issue in the future with these maintenance tips:
- Install CO detectors on every level and near bedrooms
- Schedule annual furnace maintenance
- Replace CO detectors every 5-7 years
- Never block furnace vents or exhaust
- Know the symptoms of CO exposure
Estimated Repair Cost
* Actual costs may vary based on the specific cause, parts needed, and system type. We provide upfront pricing before any work begins.
Need Help With This Issue?
Our expert technicians can diagnose and fix this problem quickly.
Call (650) 540-7205Book Service OnlineQuick Facts
- Category:heating
- Urgency:Emergency
- DIY Fixes:1 of 4 causes
- Est. Cost:$0 (detector batteries) to $300-$500 (inspection/repair) to $1,500+ (heat exchanger/replacement)
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