How A Poorly Maintained And Operating Water Heater Can Cause Legionnaires’ Disease, And How To Avoid It

You might have heard about Legionnaires’ disease on the news or in the paper. After all, there have been many stories over the years about air conditioning systems in hotels, office buildings and shopping centres, transmitting this severe form of pneumonia to its patrons and often with severe symptoms!

What many people don’t realise is that Legionnaires’ disease can also be spread through poorly maintained home water heaters. Sound a bit scary? It doesn’t need to be. There are some easy ways to avoid the growth of Legionnaires’ disease in hot water and they don’t involve spending a lot of money or vacating your house.

Firstly, what is Legionnaires’ disease?

Legionnaires’ disease is a respiratory disease that can cause a type of pneumonia deriving from a bacterium known as Legionella. While Legionnaires’ disease isn’t contagious through person to person contact, you can catch it through inhaling the Legionella bacteria from other sources like poorly maintained air-conditioners, residential hot water systems and swimming pools.

The important thing to know about the Legionella bacteria is that it spreads in water. It multiplies when temperatures are between 20-45°C.The bacteria are dormant below 20°C and can’t survive above 60°C.

What are the symptoms of the disease?

The bacterium also causes Pontiac fever, a milder illness that’s similar to the flu. Legionnaires’ disease usually develops two to ten days after being exposed to the bacteria. Symptoms include fever, gastrointestinal issues, chest pain, shortness of breath and even confusion. Legionnaires’ disease is not usually fatal if caught early and can be treated with antibiotics. If you display these symptoms and think you might have been exposed, you should go to your doctor straight away. The earlier it’s caught, the easier it is to treat and less likely there will be any complications.

While anyone can develop Legionnaires’ disease, some are more at risk, depending on a number of factors. The older you are, the more likely you are to catch the disease. If you’re a smoker, alcoholic or have existing illness such as cancer, diabetes, chronic respiratory or kidney disease where your immune system is weakened, your chances of becoming infected multiplied. For people at high risk, prompt
treatment is critical.

Why is Legionnaires’ disease a risk for home water heaters?

While many people associate the disease with commercial environments, in a home setting, people can get sick by inhaling droplets of Legionnaires’ disease in hot water from the infected tank while showering. Less commonly, you can get sick through aspiration of drinking water containing the bacteria if the water accidentally goes into the lungs while drinking.

How to avoid Legionella in your water heater and protect you and your family

1. Keep your water heater set to a minimum of 60°C to prevent the growth of Legionnaires’ disease in hot water

Your plumber will know to set up your system to run at 60°C when your heater is installed. We recommend you to leave the temperature gauge as it was set by your plumber, just to be safe. And don’t worry about scalding. Tempering or mixing valves are used to prevent injury by adding in cold water – but only after the hot water leaves your tank. Plumbers will set the valve to deliver water at 50°C to your hot water tap.

2. Don’t turn your hot water heater off or turn the temperature down – ever!

Turning the temperature down on your hot water tank to reduce costs should be avoided as it can create the perfect conditions for the bacteria to grow. When going on holidays, some people might also turn off their water heater to save costs. This should also be avoided for the same reasons.

3. Flush your systems once a year to rid systems of build-up and debris

Sediment can collect at the bottom of a neglected hot water tank. This can also be a breeding ground for the Legionella bacteria. A properly maintained tank can also help prolong your water heater’s life and prevent malfunctions.

4. Stagnant water favours Legionella bacteria growth

To reduce this risk, you should flush out infrequently used outlets regularly and clean and de-scale your showerheads a few times a year. If possible, removing dead legs/dead ends in pipework will also avoid stagnant water which can harbour the Legionella bacteria.

5. Consider continuous flow hot water heaters

Another solution is to install a continuous flow water heater. As these systems are tankless, there is nowhere for the Legionella bacteria to grow and multiply. These systems also never run out of hot water – another bonus!

Preventative maintenance is something Hot Water Specialists specialise in. Get in touch today if you would like information on how to ensure your hot water system is maintained and operating as it should be.