Silent but Deadly: The Backdraft Phenomenon

When you think of the word backdraft, you may be imaging fire bursting through a door or winding in a dangerous explosion sending firefighters launching backward. We’ve seen this in movies and are aware of the serious risk this type of backdraft presents. While not as dramatic as the fireballs bursting through doors, there is another type of backdraft that also poses a serious risk. The backdraft we are thinking of occurs when carbon monoxide or other gases from our furnaces, boilers or water heaters are not properly ventilated and they make their way back into our homes or buildings. This type of backdraft can affect the efficiency of mechanical systems but, more importantly, can lead to the concentration of harmful gases.

Water heaters are the most common cause of backdraft

Many appliances use combustion to function and in the process of combustion, carbon monoxide is produced. These appliances are fitted with ventilation ducts and flues or have valves to prevent the backdraft of carbon monoxide or combustion gases and air exchange systems in our HVAC systems work to balance the air pressure and ensure that these gases ventilated. However, with all these components in place, backdrafting can still be an issue in many homes and commercial buildings. There are a few ways that we can determine if backdrafting is occurring.

A carbon monoxide detector can be the first line of defense against the risks of backdrafting

The most straight forward method of detecting the occurrence of backdraft is to utilize a carbon monoxide detector. A carbon monoxide detector will sound an alarm when carbon monoxide levels become dangerously high in a space. If the meter registers high levels of carbon monoxide, backdrafting is likely occurring and steps should be taken to mitigate this immediately. Another more simple way to determine if backdrafting is an issue is to use a smoke stick or incense stick to see if harmful gases are properly being ventilated. If you light the stick near a ventilation flue and the smoke is not pulled out through the ducts, exhaust fumes are also likely not being ventilated out through the ventilation system. Another sign to look out for is excessive heat around exhaust vents. Plastic gaskets or grommets can show signs of melting. If you detect any signs of backdraft occurring or concentration of carbon monoxide, this can be a serious issue and an expert should be contacted immediately.

Flues and ventilation must be configured properly to prevent backdrafting

Now, we understand what backdraft is and why it is dangerous. Let’s look at what causes backdrafting and how we can prevent it from happening. Gas water heaters are a common cause of backdrafting. Gas water heaters installed in storage closets or other spaces are not properly ventilated. This can cause concentration of carbon monoxide or combustion gases. To use gas-fired water heaters safely, they should be inspected to ensure they are properly sealed, are not leaking gas and are properly ventilated.

LG’s Hydro Kit provides hot water without the risk of backdrafting

LG Therma V for residential spaces and the LG Hydro Kit for commercial spaces are efficient alternatives for hot water sources as they are designed not to cause backdrafting. While many of us are more focused on sealing our buildings to improve HVAC system efficiency and reduce the costs of heating and cooling, when a building is too tightly sealed, it can disrupt the natural ventilation flow. When the balance of air pressure is not appropriately maintained, harmful gases are not able to be removed from indoors. Solutions such as LG AHUs can efficiently maintain air pressure at desired levels throughout a commercial space and provide fresh air to the indoor environment. Appliances that use combustion gases are designed to remove carbon monoxide and other gases from an environment through ventilation flues or ducts. If these ducts are blocked or, perhaps, not configured appropriately, backdrafting will be inevitably become an issue.

It is imperative for the health of occupants in any space to protect against backdrafting. If you suspect that backdrafting is occurring in your home or facility, be sure to have your appliances and ventilation systems inspected a soon as possible. We strive to provide effective, efficient HVAC product that creates a healthy environment in any space and hope you are able to maintain a healthy environment too, wherever you are.

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