Carbon monoxide

Carbon monoxide (CO) is one of the by-products of natural gas combustion, the process that occurs in a gas heater. It is a colourless, odourless and tasteless gas that can cause death or serious illness.

Carbon monoxide poisoning can occur in any home or building with gas heating appliances. This includes newer models. Sadly, in the past decade, nine Victorians have died from carbon monoxide poisoning.

Service your gas appliance once every two years

The best way to make sure your heater or any gas appliance is safe is to have it serviced at least once every two years by a specialised plumber called a gasfitter.

As part of servicing your gas appliance, the gasfitter will test for carbon monoxide spillage and negative pressure – two key risks for CO poisoning.

If the gasfitter identifies CO spillage at your property, it must be rectified immediately as exposure to CO can put your life at risk. Your appliance may need to be repaired or disconnected.

If the gasfitter identifies negative pressure at your property, this also needs to be rectified. The gasfitter may need to install additional ventilation.

Use the right kind of gasfitter

For your appliance servicing, you should always use a gasfitter who is registered or licensed in Type A appliance servicing work.

You can ask the gasfitter about their qualifications and check the back of their ID card to make sure they are licensed or registered in Type A appliance servicing work.

If you are not sure if you are engaging the right type of gasfitter to undertake this work, you can check their type of licence or registration on our Find a practitioner tool.

After they have done the servicing work, the gasfitter must provide you with a compliance certificate if the total value of the work is $750 or more. If your work needs a compliance certificate, this must be provided by a licensed gasfitter.

Carbon monoxide spillage tests

Carbon monoxide should always leave a house through the heater’s flue. In appliances with an open flue, negative pressure can draw the carbon monoxide from the flue back into the room, rather than allowing it to escape to the outside. This can cause the levels of carbon monoxide to build up in the air.

The carbon monoxide spillage test checks the key areas of your gas heater and room for spillage. Your gasfitter will use a probe to check different parts of the heater and the room it is in to make sure there is no carbon monoxide in the air.

If your gasfitter detects carbon monoxide, they will take specific action to check whether the problem is caused by negative pressure or a fault with your heater.

If the carbon monoxide spillage cannot be rectified because there is a fault with your heater, the gasfitter must disable its operation. This might make you cold for a few days, but will keep you safe.

Negative pressure tests

Negative pressure is created when extraction fans (including kitchen rangehoods) remove air from a building more quickly than it can be replaced. When this happens, air can be drawn back down your heater’s flue, causing carbon monoxide and other gases to enter the room (instead of being vented outside as they should be).

If your gasfitter identifies negative pressure, this must be rectified. This could involve ensuring openings in your home or building are clear (such as removing flywire from behind vents, which is common in older homes). You may need additional ventilation installed in the room. Your gasfitter should be able to carry out the work required.

Can I keep using my gas heater?

If your gasfitter finds that negative pressure is causing your heater to spill carbon monoxide, but there is no other fault, we strongly advise you stop using your heater until additional ventilation can be installed.

If you do choose to keep using your heater, there are two important safety precautions:

  • leave a window open in the rooms where your extraction fans are located
  • switch off all your extraction fans while your heater is operating.

Refusing to have ventilation installed

Your plumber must notify the VBA of a failed negative pressure test if you refuse to allow them to rectify the negative pressure situation. They will also pass your details on to the VBA.

After we receive your details, we will contact you directly. This is due to the potential safety risks to current and future occupants of the home if the negative pressure issue is not permanently rectified.