What temperature should my boiler be in winter?

Setting the right boiler temperature for winter

Setting your boiler temperature correctly during the winter is a balancing act between ensuring your home is warm enough while making sure that you aren’t overusing energy and driving your bills up as a result.

Changing the temperature of your boiler in winter isn’t hard, whether it’s a combi or cylinder boiler.

Get it right and you can save money, as well as keep cosy as the nights draw in and the mercury plunges.

What are the optimal temperature ranges for cold weather?

The optimal temperature for a boiler in cold weather is between 60ºC (140ºF) and 70ºC (158ºF).

At the lower end of this range, your boiler will still have what’s called a 60ºC flow temperature, the temperature at which water is sent to the radiators in your home, warm enough to heat most homes.

This in turn means the temperature of the water going back to your boiler (called the return temperature) will be lower, which means the boiler will run more efficiently.

You can lower the flow temperature to between 50ºC and 55ºC during milder months.

This temperature level affects heating. Hot water should be set at around 50ºC. Any hotter and it could lead to scaldingly hot water coming out of your pipes.

Balancing Comfort and Cost: How Boiler Temperature Affects Your Heating Bill

Boiler temperature is a key factor in determining how much you pay for your energy.

Boiler temperature is not the same as the temperature controlled by a thermostat or radiator valve.

The latter control when your heating comes on, while the former accounts for the temperature of the water flowing through your heating system.

Getting the balance right between comfort and cost is essential.

Turning boiler temperatures down does save money, with the Energy Saving Trust suggesting savings of anywhere between 9% and 13%.

However, this has to be considered against whether dropping the temperature makes rooms too cold to be comfortable, something especially important if any residents suffer from illness.

You can also save money on your energy bills by setting timers, installing a smart thermostat and insulating your walls and loft.

Read our handy guide to find out more about saving on energy bills at home.

When should I think about adjusting the temperature on my boiler?

Adjust the temperature of your boiler ahead of cold weather and turn on your heating to see how the temperature feels.

By doing so, you’ll have a clear idea of whether it feels too cold inside and whether you should raise it further to ensure greater comfort.

You should turn your boiler on for winter once it starts to feel uncomfortably cold in the home.

This is obviously down to personal preference and any concerns about paying higher energy bills.

You can invest in electric blankets to mitigate the early cold, but it’s best to have your heating on once the temperature outside slides.

It’s always worth paying to have your boiler serviced in the summer months so that it works as efficiently as possible.

Such services are available for a standalone fee or are almost always offered as standard with boiler cover.

Special Considerations for Different Boiler Types

Depending on what kind of boiler you have, there will be special considerations for each when it comes to adjusting temperature:

Combi boilers

Combi boilers have two settings options, covering hot water and heating.

To change the flow temperature, you’ll need to tweak the latter, which can usually be done next to the radiator symbol on the boiler’s display or via a dial on older models.

Cylinder boilers

These boilers only have one control dial. Adjust this accordingly to get higher or lower flow temperature

High-efficiency condensing boilers

If you have a highly efficient condensing builder and live in a newer home with triple glazing and good insulation throughout, you can drop the flow temperature as low as 45ºC to achieve maximum efficiency.

Water temperature

This is different to the flow temperature for your heating. Water temperature should be set at a maximum of 50ºC to prevent scalding.