- Adjusting the temperature of your boiler can help, but lowering it too much is dangerous
By adjusting the supply temperature of your boiler you can save up to €57 per year on your gas bill, but lowering the temperature too low can be dangerous.
If you’re not sure what your boiler’s supply temperature setting is, you’re not alone.
Basically, it’s a way to adjust the temperature of the water leaving your water heater.
Many people are unaware that this setting even exists, and many more are reluctant to adjust the settings on their boiler when they do something wrong.
But changing boiler flow settings is a simple process that can save you up to £57.04 per year on your energy bills, according to research.
Most boilers have a flow setting between 70c and 80c when first installed. This can be much hotter than necessary to perform tasks such as heating radiators.
Let it flow: By adjusting the flow temperature of your boiler you can save money on your energy bill
A statement from EDF states: ‘At lower supply temperatures, the combination boiler is more often in condensation mode. This means it can capture more heat and recycle it back into the system.”
Lowering the supply temperature of your combi boiler to 50 degrees Celsius could mean you can save up to 8 percent on the average annual household gas bill, according to research published by the Heating and Hotwater Industry Council.
The typical annual gas bill is £828.70, made up of £713 in gas and £115.70 in standing charges.
This means that adjusting your supply temperature can save up to €57.04 per year.
However, this must be done with caution.
Too low a temperature can promote the build-up of harmful bacteria, such as Legionella pneumophila, which causes Legionnaires’ disease.
Some experts believe that 50 degrees Celsius is too low and they want to keep central heating systems more hygienic by ensuring boiler supply temperatures remain above 60 degrees Celsius.
Ryan Gill, chief technical researcher at boiler experts Boxt, said: ‘As the weather gets colder, it can be confusing trying to figure out which setting to adjust your boiler to while keeping an eye on your energy bill.
‘You can lower the supply temperature of your boiler and save money without sacrificing too much comfort. However, it is important to know that the optimal temperature for your boiler usually depends on the brand and type of boiler.
‘For example, with combination boilers the supply temperature may not be set lower than 55 degrees Celsius. For those who have a system or standard boiler with a separate hot water boiler, this should be kept at a minimum of 60 degrees Celsius.
‘Setting the temperature below these levels can promote the growth of bacteria, posing a potential health risk to you and your family. In addition, if the supply temperature is too low, your radiators may not heat your home sufficiently.’
This means that the aforementioned savings by lowering the supply temperature of your boiler may not be safe in practice.
The possible savings can also vary, for example due to the efficiency of your central heating boiler.
How to adjust the supply temperature of your boiler
On traditional boilers with a hot water cylinder, you only need to adjust one setting to adjust your flow setting.
On smaller combination boilers you will probably have two settings: one for hot water and one for radiators.
You may not be able to set your flow rate to a specific temperature because your boiler may have a different design, for example a dial with temperatures from one to six.
If you are in doubt, ask your installer next time he/she carries out an annual boiler safety check.