MythBuster: Legionnaire’s Disease

June 5 2017

James Patten


One of the most popular myths about evaporative cooling is that it’s bad for your health. In recent years, there have been some occasional outbreaks of Legionnaire’s Disease that raised concerns about the possibility of links between the disease and air conditioning units.

Evaporative cooling units, however, aren’t the cause of the disease.

What is Legionnaire’s Disease?

Caused by a bacteria typically found in bodies of water, Legionella Pneumophila, the disease can cause fever, chills, fatigue, muscle ache, headache, and decreased appetite. Comprehensive tests might be needed to distinguish it from other illnesses.

The disease is contracted by inhaling fine mist from contaminated water sources, which means that any evaporative cooling units with proper maintenance can avoid these contaminants.

Female doctor with the stethoscope holding heart


What are the Dangers from Evaporative Cooling Units?

When evaporative cooling units are poorly maintained, there is a chance of health hazards and pollutants being spread through the air. As air conditioning units are extremely effective in circulating air which, unfortunately, means that hazards can be quickly transmitted throughout a building. Typically including allergens and bacteria, these hazards aren’t derived from air conditioning units but from their poor cleaning and maintenance.

Evaporative cooling units aren’t the cause of Legionnaire’s Disease; poor design and poor maintenance are risk factors, and protecting your unit from contamination is the first step.


Regular Maintenance

The proper maintenance and cleaning of evaporative cooling units is the most effective way of to ensure these hazards are spread through the air. Outlets and intakes require regular cleaning to avoid issues relating to asthma or allergies, but their regular cleaning also ensures they function properly. A dust build-up prevents air conditioning unit components from functioning properly.

Through consistent cleaning and maintenance, illnesses such as Legionnaire’s disease aren’t spread. Contaminants and agents that cause diseases, like mould, also don’t build up to dangerous levels. Your evaporative cooling unit should be serviced by a professional at least once a year to ensure its proper functioning.

Technician - Engineer investigate Repairing Air Conditioner

Evaporative cooling units need to be serviced before seasons of heavy use, particularly because they might have been inactive for a long period and bacteria could have built up and multiplied. To prevent bacteria like legionella from building up on your air conditioning unit, you can ensure that your unit isn’t completely idle. The water in water-based units unit should shouldn’t be stagnant or kept at temperatures in which legionella can thrive. Water should be kept at 60°C or above or cooled at less than 20°C.

Having a professional service your evaporative cooling units will ensure that the system is properly cleaned and working as it should, preventing bacteria from building up and being spread through the air. At Heritage Heating & Cooling we always ensure that your industrial and commercial evaporative cooling units are of the highest quality for your health and comfort.

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