How do I reduce carbon monoxide in my furnace?

Q: What causes high carbon monoxide in a furnace?

Your furnaces heat exchanger is where the process of combustion occurs. The air from the furnace circulates around the outside of the heat exchanger. If theres a crack in the exchanger, the air runs across the burner and causes incomplete combustion and, in turn, creates a carbon monoxide buildup.

Carbon monoxide could be spilling into your home while your gas heater is running.

Table of Contents Show

Service your gas heater for winter
Are you a homeowner?
Are you a tenant, rental provider or real estate agent?
Use your gas heater safely
Is carbon monoxide (CO) making you sick?
Act quickly if you think your heater could be making people sick
Finding a licensed gasfitter
The benefits to you
What causes high carbon monoxide in a furnace?
How do I know if my furnace is leaking carbon monoxide?
Is carbon monoxide poisoning by furnace common?
How do you neutralize carbon monoxide?

It doesn’t make a sound. You can’t see it or smell it.

Watch all our Be Sure – carbon monoxide safety videos.

All gas heaters can spill carbon monoxide (CO) – a gas you can’t see or smell that can make you seriously sick or kill you.

To be sure your gas heater is safe, you should:

have it serviced at least once every two years, by a qualified gasfitter
check for safety advice – some heaters need fresh air flow to operate safely.

Service your gas heater for winter

You won’t be able to tell if your heater is leaking carbon monoxide – because you can’t see it or smell it.

Be sure your gas heater is safe. Have it serviced at least once every two years by a qualified gasfitter.

Are you a homeowner?

Find a qualified gasfitter as if you would find your local tradesperson; online or in your local paper. Check their licence to make sure they have the required qualifications to complete the service and testing. Read more about this below.

Are you a tenant, rental provider or real estate agent?

Victoria’s new rental laws came into effect on 29 March 2021.

Consumer Affairs Victoria (CAV) is the agency responsible for these regulations. The CAV website provides detailed summaries and guides on the full range of changes included in the new renting regulations.

Under the new laws rental providers (previously referred to as landlords) have certain responsibilities for gas and electrical safety.

The rental provider must ensure a gas safety check of all gas installations and fittings on the premises is conducted every two years by a licensed or registered gasfitter who is endorsed in the specialised class of Type A gas appliances servicing work (Gas Serving Type A on the Plumbers Identity Card).

Find out more about your rights and responsibilities under the new rental laws.

Use your gas heater safely

Check if a safety alert has been issued for your gas heater.
Don’t use kitchen rangehoods or exhaust fans at the same time as your heater. This can create what is known as a negative pressure environment, where carbon monoxide is drawn into living spaces.
Don’t leave your gas heater on overnight, or for extensive periods.
Install a carbon monoxide alarm as a back-up measure.
If your heater is very old, consider replacing it.
Never bring portable outdoor gas appliances indoors.

Learn more about heating your home safely with gas.

Is carbon monoxide (CO) making you sick?

CO building up inside your home can make you sick for a short time, have long-term health effects or even kill you and your family quickly.

Some of the symptoms are similar to cold symptoms, common in winter. This can make it difficult for a doctor to diagnose that you are suffering from carbon monoxide poisoning.

If you notice any of the following symptoms, they could be caused by carbon monoxide leaking from your heater.

Dizziness
Feeling sick or nauseous
Headaches
People and/or pets getting sick at the same time
Feeling unwell only when you’re at home.

Act quickly if you think your heater could be making people sick

Call Nurse-on-Call, see a doctor or dial 000 in an emergency
Leave the house immediately and get into the fresh air
Turn off all gas appliances straight away, open windows and doors to let fresh air into the house
Do not use your heater until you’ve had it checked by a qualified gasfitter.

Finding a licensed gasfitter

Type A Gasfitters

There are two different types of gas appliances – Type A and Type B appliances.

Type A appliances include domestic and light commercial type appliances such cookers, space heaters, central heaters, water heaters, catering equipment and leisure appliances. So, when looking to service and repair your gas heater, be sure it’s done by a licensed gasfitter endorsed in the specialised class Gas Servicing Type A.

To conduct routine servicing and CO checks, the licence needs to show the ‘Gas servicing type-A’ (circled in red below) accreditation.

Look out for the licence/s below when choosing a gasfitter to carry out the work. Check that they are qualified to carry out Type A appliance servicing.

The benefits to you

Training and competency – to be a licensed gasfitter, a person must have undertaken the appropriate training to complete gas work safely, including having passed exams for competency and being registered with the VBA.
Licensed gasfitters must have insurance – providing a six (6) year warranty on the work they perform.
Preserve your manufacturer’s warranty conditions – if appliance installation work is carried out by a licensed tradesperson, your manufacturer’s warranty conditions are not breached.

What causes high carbon monoxide in a furnace?

Your furnace's heat exchanger is where the process of combustion occurs. The air from the furnace circulates around the outside of the heat exchanger. If there's a crack in the exchanger, the air runs across the burner and causes incomplete combustion and, in turn, creates a carbon monoxide buildup.

How do I know if my furnace is leaking carbon monoxide?

Signs of Carbon Monoxide Leaks.

Soot: You may notice soot-like stains on your furnace. ... .

Smell: While carbon monoxide doesn't emit odor, it may get accompanied by other exhaust gases that produce an odor..

A yellow burner flame: The pilot flame may produce an unusual yellow flame instead of the normal blue one..

Is carbon monoxide poisoning by furnace common?

Carbon Monoxide poisoning kills 400 Americans every year and sends 20,000 to the hospital, according to the CDC. Leaking furnaces or boilers are one of the most common causes of deadly carbon monoxide poisoning— every year without fail.

How do you neutralize carbon monoxide?

To date, many different methods have been developed for neutralizing carbon monoxide in gas emissions. The most widely used are absorption, thermal, adsorption and catalytic methods.