What is the optimum temperature to set a boiler?

Trying to figure out what setting to adjust your boiler to can seem a bit confusing, particularly because there's so much information out there online. However, the optimum temperature for your boiler will usually depend on the boiler's make and type.

We'll cover the best potential temperature settings for your boiler while also giving you some great heating system tips to keep in mind.

Setting the perfect boiler temperature

Temperature settings will vary depending on your heating system manufacturer's requirements. Although we have provided general central heating system suggestions below, we highly recommend that you refer to your manual as your final authority. 

The higher the temperature set does not necessarily mean the quicker your home will heat. This can unnecessarily increase your energy bills and potentially decrease your boiler’s overall efficiency. 

Typically you'd set the radiator heating output temperature to between 60 and 75°C. Adjusting this temperature too much can affect its efficiency. 

The ideal hot water temperature for a Combi boiler and hot water cylinder is around 60°C.

Looking Out For Legionnaires' Disease

Having hot water isn't only for your comfort. Setting your cylinder thermostat or boiler's temperature lower than 60°C can be risky due to the increased risk of Legionnaires' disease. 

Legionella thrives in temperatures between 20-45°C but cannot survive temperatures above 60°C. Legionnaires' can become so severe that many require hospitalisation. While this is unlikely to occur in the first place, keep this in mind.

Creating the ideal room temperature

So, we've spoken about the ideal temperatures for modern boilers. But what about your room? What kind of temperature should you be aiming for? 

This can be subjective as people have different cold and heat tolerances, but we'll provide general guidelines.

Typically, you'd want your room temperature to be anywhere from 18 to 21°C. Bear in mind that the set temperature of your radiator is very different from the room temperature. For example, while you may set your thermostat to about 20°C, you can set up your boiler to 75°C.

Discover our guide on the ideal room temperature in the UK for more information on this topic.

Our three top tips for home heating

You need to know a few things to ensure that your central heating is at its most efficient. In the next few paragraphs, we'll be taking you through some (not so common) common knowledge.

Lower your temperature

This tip may seem obvious but is worth repeating: if you want to get the most out of your central heating, set your room thermostat lower. Ultimately, it's about being smart with your energy usage and what you need. 

However, make sure to follow the above guidelines and keep your boiler at a safe temperature to prevent bacteria growth.

Bedrooms don't need as much heating

Did you know that you can set your bedroom 2°C lower than the rest of the house? That's the ideal sleeping condition for the average person. However, this can change for children and elderly individuals, so make sure to find a temperature that suits you.

Let your radiator heat appropriately

Make sure your radiator isn't blocked by a table, chair, or some other appliance, as this can inhibit its efficiency by blocking the hot air supply. Radiators should be installed in their own space out of the way of other objects.

Setting your thermostatic radiator valves

If you aren't familiar with the term, thermostatic radiator valves (TRVs for short) control the temperature in individual rooms. You can even get "smart" radiator valves that you can remotely control from your mobile phone.

When using these, we suggest you set them no higher than at a setting of 2 or 3. Anything higher than this is usually wasteful.

We're seasoned professionals in the boiler business with a network of over 8000 Gas Safe engineers across the United Kingdom. For more information on the topic or anything boiler related, make the most of our Live Chat function to chat with one of our team.

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