Vent Free Propane Heater Safety Guide

If you and your family are experiencing harsh winter colds, you may be thinking about getting a space heater for your home. Propane heaters, vented and vent-free, are a viable option.

They tend to be more cost-efficient than their electric counterparts. However, that comes with its only hurdles you need to overcome when using an indoor propane heater. So are vent-free propane heaters safe?

Vent-free propane heaters are safe to use, provided you keep your heater maintained. Even though they are vent-free, it is still highly recommended to have ventilation in the rooms if you decide to purchase these heaters.

You can achieve this by having an open window or running your centralized air to vent to help vent out the carbon dioxide, the large amounts of water vapor, and the harmful carbon monoxide of faulty propane heaters.

This article will answer any questions you may have before purchasing extra comfort for your family. It will also provide a hefty amount of safety tips you should use when buying and setting up your heaters to stay warm during this cold weather.

Are Vent Free Propane Heaters Safe?

Non-vented propane heaters have had a surprisingly clean record when it comes to safety concerns. These heaters, while not truly perfect, are designed to burn as cleanly as possible.

Properly installed and maintained vent-free propane heaters provide near-complete combustion. This means the propane burning should primarily produce carbon dioxide and water vapor while releasing very little carbon monoxide.

Carbon dioxide and water vapor are considered natural and non-toxic. We tend to deal with these chemicals daily and do not even notice.

However, carbon monoxide is highly toxic and can severely injure you or worse if you are left in a confined space long enough.

It is highly recommended to have some ventilation if you decide to use one of these heaters in your household. Not only will this help prevent the rare occurrence of carbon monoxide poisoning. However, non-vented propane heaters produce a lot of water vapor into the atmosphere of your home.

Depending on the size of your chosen heater, it can make up to 1 quarter gallon of water vapor into your residence every hour. This can cause damage to your walls and furniture.

The good thing is that most vent-free propane heaters come with an ODS or an Oxygen Depletion Sensor. This sensor will automatically shut down your heater if it detects the oxygen level drop below 18%.

The sensor will ensure that even in the rare circumstance that your vent-free heater produces more carbon monoxide than it should and that the owner doesn’t follow proper ventilation of the room it is being used in, the heater will automatically shut off.

If this happens, it is advised to allow your heater to stay off for at least an hour before turning it back on again.

Can You Get Carbon Monoxide Poisoning From A Propane Heater?

Carbon monoxide poisoning is responsible for nearly 25% of all propane-related deaths. Carbon monoxide is the result of an incomplete burn of propane.

Properly maintained propane heaters would produce a clean burn resulting in carbon dioxide being released instead, non-toxic.

As long as you follow the ventilation instructions that come with these heaters, the risk of carbon monoxide poison is fairly low. 

Not only that, but carbon monoxide is a deadly toxic gas that is undetectable by the smell that can harm or kill animals, plants, and people alike.

Propane gas is not the only source of carbon monoxide. Any natural gas that is burning wrong will result in the production of carbon monoxide.

While operating a propane heater indoors, you should know the signs of carbon monoxide poisoning just in case your ODS is malfunctioning. Many of these symptoms include:

  • Headaches
  • Dizziness
  • Nausea
  • Breathlessness
  • Collapse
  • Loss of consciousness

The signs of carbon monoxide poisoning adhere to the list provided. So if you use vented or vent-free propane heaters in your home, be sure to look out for these symptoms in yourself and your family.

Keep in mind that investing in a carbon monoxide detector would be wise with all of this information. This will ensure better safety over figuring out if you have it or not. It is best to get at least one or two in the house at least 5-feet above the floor for better protection.   

How To Tell If Your Propane Heater Is Leaking Carbon Monoxide

The most obvious signs that your indoor propane heater is leaking carbon monoxide are easy to tell if you inspect your heater while it is on or off.

While it is on, if your propane is burning any other color than blue, such as a yellow or orange color, then your heater is burning impurely and is producing carbon monoxide. Please turn it off and call a professional immediately to avoid any further issues. 

While carbon monoxide does not produce any smell, the cause of the nasty burn may have a scent. If you start to detect a weird odor in the room using your heater, turn it off immediately.

If you inspected your heater while it is off and you see soot of any kind in or around your flame, your heater is burning impurely.

If any of these cases occur, call a propane technician to come out and inspect your heater and possibly your carbon monoxide detectors as well.

Are Propane Heaters Safe To Use Indoors?

Propane heaters are generally not recommended to be used solely indoors. However, they work great in places with openings for ventilation to the outside air, like a garage, porch, or shed.

That being said, propane heaters do provide faster heat at a lower cost than electric heaters. But you have to give that heater the proper ventilation it needs to prevent harm to yourself and your family.

Safety Tips When Using Your Propane Heater

When used, set up, and maintained properly, propane heaters are safe for use indoors. Even still, this article will provide some safety tips to follow to help this process:

  • Make sure the heater you purchase has safety features such as an ODS (Oxygen Depletion Sensor), a high-temperature coated safety guard, overheat protection, and an automatic shut-off switch if your heater is accidentally tipped over.
  • Only purchase space heaters that are duly certified by looking for the proper markings from the following safety testing companies: Underwriters Laboratories (UL), Intertek (ETL), or a CSA International certification.
  • Carefully read the user manual before setting up and using your vent-free propane heater.
  • Be sure to have proper ventilation for even vent-free propane heaters. Do this by opening a window or running your centralized air. For a vented heater, make sure that their exhaust is properly vented outside.
  • Make sure your indoor propane heater is set up in a space that is away from heavy foot traffic, on a flat surface to help prevent tipping, and give the heater a minimum of 3 feet away from anything that may be combustible due to heat, such as bedding, curtains, and furniture, etc.
  • Never place anything on top of your propane heater. 
  • Install smoke and carbon monoxide detectors in the rooms you plan on using your heater as a backup sensor to the ODS that will come with.
  • If you decide to get a portable heater, be sure never to leave it unattended. Turn it off whenever you leave the room, even if it is just for a minute or two. 
  • Avoid using the heater all day, as this will help prevent malfunctions.
  • If your indoor propane heater has a yellow or orange flame instead of blue, turn it off immediately and contact a propane technician.
  • Never use an indoor heater to dry clothes or wet spots on carpet or furniture.
  • Keep children and pets away from indoor space heaters.
  • Properly maintain your indoor propane heaters according to the manufacturer’s instructions provided. Make sure your heater is turned off and cool to the touch before doing anything with it.
  • Use your hose attachment for your vacuum cleaner to clean up carefully and dust on the outside of the propane heater and on its grills.
  • Never spray any air fresheners, deodorants, aerosol sprays, or hair spray around your propane heater as these are flammable and can catch your house on fire.
  • Make sure all of the pathways and exits are clear when using your indoor propane heater for a quick exit if there is a fire.
  • Ensure you know about proper propane safety before you begin using your indoor propane heater.

Final Thoughts

If you are looking for a cost-effective option to keep your family warm and comfortable during the cold seasons, a vented or vent-free propane heater may be your best choice. However, if you purchase any heater of any kind, follow the safety instructions provided with your heater and the safety tips listed in this article to help prevent losing your home or worse.

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Hubert Miles

I've been conducting home inspections for 17 years. I'm a licensed Home Inspector, Certified Master Inspector (CMI), and FHA 203k Consultant. I started to help people better understand the home inspection process and answer questions about homeownership and home maintenance.
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