If you’ve asked yourself what temperature a boiler should be set at, then you’ve come to the right place, as I have pondered this very question and have the answer.

Last week I shared with you my first really easy and quick way to save energy, to help save you both money and the environment.  As I do love a good win-win, I’m back again today, as promised, with my second tip.

This time, let’s look at how you can save energy with your boiler, by setting it at the right temperature.

What Temperature Should A Boiler Be Set At?

What temperature should a boiler be set at?

The average boiler hot water thermostat in the UK is set to 65ºC. This is very inefficient and a waste of energy and money. At this temperature, you have to cool the water that you’ve spent money heating with cold water to be able to use it. It’s also completely inefficient as heat loss from your boiler/hot water cylinder is also increased.

I’d recommend checking your boiler or even just having a think about how hot your hot water taps are.  Do you find you have to add cold water when you’re washing your hands to bring it to a comfortable level?  Then your boiler temperature is probably set too high.  At 60ºC water is still sufficiently hot for almost all domestic uses. So go and turn it down to 60ºC (but not before you’ve read the safety advice below).  

It’ll take less than a minute to do and you’ll have a nice warm glow. Your boiler won’t have to work as hard, prolonging its life. You’ll also save both the environment and money. It’s estimated that you’ll save around £30 a year if you turn your boiler temperature down from 65ºC to 60ºC. This is a healthy amount to save for very little work.

An Important Word of Warning

Don’t set your boiler temperature too low. This is because at low temperatures the bacteria responsible for Legionnaires’ Disease, a potentially fatal lung infection spread through the inhalation of water bourne particles, can thrive and multiply.  

According to the Health & Safety Executive, the legionella bacteria (which cause the disease) require a temperature of between 20-45ºC to grow. The bacteria do not survive at temperatures above 60°C. Therefore, by setting your boiler temperature to 60ºC you’re well out of danger.

What About The Radiator Temperature On The Boiler?

For combi boilers, it’s recommended that you set the radiator output temperature on your boiler at 75°C. This is the optimum temperature for your boiler to heat your home quickly and efficiently.

What About The Room Temperature?

The optimum room temperature is around 18 to 21°C. This temperature range is the most comfortable and healthy for day-to-day living. Here are some tips on how to set the timer on your boiler if you need some advice.

So there you go: turning down the temperature on your boiler a few degrees will save you a pretty penny, and the environment. And you’ll also reduce the risk of scalding from your bathroom or kitchen taps. This makes this tip a triple win!

I’ve got more easy energy-saving tips right here in my archive if you are looking for more energy-saving inspiration.

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