What temperature should my boiler be in winter?
Get your boiler temperature right and you can save money, as well as keep cosy in the cold weather. Here's how...
Key takeaways
Set the flow temperature between 60ºC and 70ºC for effective heating in winter, and lower it to 50ºC to 55ºC in milder weather.
Adjusting boiler temperature can save 9% to 13% on energy bills while maintaining a warm home.
Adjust boiler settings before winter and consider summer servicing for peak efficiency.
With the right boiler temperature settings, you can strike a balance between cosy warmth and managing your energy costs. The correct boiler temperature is crucial for maintaining a comfortable and cost-efficient home environment throughout the colder months.
Optimal boiler temperature settings
On modern boilers, you can set different temperatures for your radiators and your hot water. By default, these are higher than you need, so adjusting the settings can keep your home warm and save you money.
Time of year | Flow temperature | Hot water temperature |
|---|---|---|
Winter | 60ºC to 70ºC | 50ºC |
Spring and Autumn | 50ºC to 55ºC | 50ºC |
If your home is well-insulated, you can push your flow temperature even lower. You can make your home more energy efficient by:
Installing cavity wall and loft insulation
Upgrading your windows from single-glazed to double-glazed (or even triple-glazed)
Draught-proof windows and doors to prevent heat escaping
If you have a health condition and need to stay warm, we'd recommend leaving your boiler settings alone to avoid risking your wellbeing.
For your hot water needs, a safe and practical setting is around 50ºC. This temperature is adequate for domestic use, ensuring that the water is hot enough for baths and showers while also preventing the risk of scalding. If you're diluting your hot water with cold water when running a bath or shower, it's probably set too high.
How much can I save by lowering my boiler's flow temperature?
Turning boiler temperatures down does save money, with the Energy Saving Trust suggesting savings of anywhere between 9% and 13%.
When to adjust boiler temperature
Adjust your boiler temperature before the cold really sets in. Ideally, you should start using your heating system when indoor temperatures begin to dip to uncomfortable levels, based on personal preference and concerns about energy costs. While alternatives such as electric blankets can provide some relief, a properly heated home is essential, particularly during extremely cold weather.
Moreover, to ensure your boiler operates at peak efficiency, consider having it serviced during the summer months. It’s always worth paying to have your boiler serviced when demand is lower, and you can ensure it's in top condition for when you need it most.
Additionally, many boiler cover plans include a free annual service to keep your boiler in tip-top shape.
What about system boilers and hot water cylinders?
Typically, these have a single control dial that regulates both heating and hot water flow temperature. The HSE recommend storing the water above 60ºC to control the risk from legionella, and the Heating Hub suggest keeping flow temperatures at 70ºC to compensate for heat losses.
Do not adjust the settings on a system boiler or hot water cylinder yourself.
You can get your boiler adapted to set different heating and hot water temperatures, meaning you can lower your flow temperature for heating and save money on your energy bills.
Energy saving measures for hot water cylinders
Insulate your hot water cylinder with jacket insulation
Add radiator reflector panels behind your radiators
What else can I do to save money on my energy bills?
Invest in a smart thermostat
Review your appliances and check how much they're costing to run
Switch to a new energy tariff if you're paying too much