Carbon monoxide alarms and your furnace: what Michigan sources advise

What Michigan officials advise about alarms

The Michigan Bureau of Fire Services, through its MI Prevention program, says to install smoke alarms and carbon monoxide detectors on every floor of your home. Its home safety checklist asks for a working CO alarm on every level. That is advice, not code text, and we have kept the two apart because many pages blur them.

We found no Michigan statute or code text requiring CO alarms in existing homes. Your local fire department can tell you whether a local rule applies to your house, and the advice above is a sound baseline either way.

The federal Consumer Product Safety Commission is more specific about placement, according to a summary of its page rather than the page itself. It advises battery-operated alarms, or alarms with battery backup, on every level of the home and outside sleeping areas, notes that interconnected alarms are best, and says that when one sounds you should get outside to fresh air and call 911.

Why the furnace is on the list

Carbon monoxide is a product of burning fuel, and a furnace burns fuel. Michigan’s gas utilities treat furnace service as the main prevention step, though each words it a little differently.

DTE says to hire a maintenance professional to check your furnace and fuel-burning appliances annually and to install CO detectors near all sleeping areas. Consumers Energy asks for a CO alarm on every floor, especially near sleeping rooms, and for your heating system and gas, oil, wood or coal appliances to be serviced by a qualified technician each year. The CDC, as we read it, says the same about annual service by a qualified technician and adds a yearly chimney check.

ENERGY STAR gives a reason from the equipment side. It recommends having a contractor do annual pre-season check-ups, with the heating check in the fall. That check includes gas connections, gas pressure, burner combustion and the heat exchanger, and it says a cracked heat exchanger can make equipment operate less safely.

Keep air and vents clear

DTE’s safety checklist says to inspect the flues of appliances to make sure they are corrosion-free, securely attached and correctly vented, and to unblock furnace room air vents, because appliances need proper air flow to burn fuel completely. Those are two things you can look at without a tool. If a flue looks loose or rusted, turn the appliance off and have a professional look.

Fuel-burning devices meant for outdoors are the other common source of trouble in a Michigan outage. Consumers Energy says never to use a generator, grill, camp stove or other fuel-burning device inside your home, basement or garage, or near a window. The CDC advice, as we read it through a summary, is to run a generator outdoors more than 20 feet from windows, doors and vents.

When an alarm sounds

Do not try to find the cause first. DTE says to leave the building immediately, get into fresh air and call 911, and not to go back in until first responders or DTE say it is safe. Consumers Energy says to leave your home right away and call 911. Michigan Gas Utilities gives the same instruction for carbon monoxide: leave the building and call 911.

SEMCO Energy Gas quotes CPSC on the call: contact the fire department or 911 and move to fresh air. SEMCO also lists symptoms that resemble flu without a fever: headache, fatigue, shortness of breath, nausea and dizziness. If several people in a house feel that way at once, and the feeling eases when they step outside, say so to the dispatcher.

The numbers are different when it is gas you smell instead. DTE says to call 911 from a safe place and then its Gas Leak Hotline at (800) 947-5000. Consumers Energy says 911 first, then 800-477-5050. Michigan Gas Utilities lists 800-401-6451 for a gas odor or a damaged line, and SEMCO lists 888-427-1427; SEMCO’s page does not mention 911 first. Treat any of these as a reason to leave first and call from outside. For a furnace that has quit, our no-heat checklist covers what is safe to check.

Rentals and the free alarm program

Renters get less clear answers. LARA’s MI Prevention FAQ says landlords are legally responsible for providing and maintaining working smoke alarms in rental units. That statement is about smoke alarms only, and says nothing about CO alarms in rentals.

Ann Arbor is the clear local example: the city has adopted an ordinance requiring carbon monoxide detection in all rental properties, and no one may lease a dwelling unit without a Certificate of Compliance in effect. The detection requirements document the city links is not covered here. In other cities, ask the housing or fire department.

The state’s free smoke alarm program has a catch. The MI Prevention page says there is no FY27 appropriation, so the Bureau of Fire Services can no longer distribute alarms. The page is undated, so ask your local fire department whether it has alarms to give out.

After a scare, and for a new furnace

If an alarm has sounded and the emergency services have cleared the house, have the furnace and other fuel-burning appliances checked by a qualified technician before you rely on them again. Ask the company for its license number and verify it, as described in how to find a licensed HVAC contractor in Michigan. A new furnace needs a permit and an inspection, covered in the furnace permit guide. To ask for a match for a repair, start at furnace repair. Replacing an old furnace is a separate decision, and the furnace replacement page explains it.

Alarms near the bedrooms matter most at night, when a furnace runs longest and nobody is awake to notice a symptom. Test your alarms on the schedule the manufacturer gives, and write the install date on each one. That makes the replacement date easy to find when the label has worn off. If an alarm chirps at intervals, treat it as a message from the device and check the manual for what that chirp pattern means, rather than pulling the battery and forgetting it.