The temperature setting on the hot water cylinder thermostat is something that most people don’t give much thought to – some don’t even know it exists. Indeed, when was the last time you checked the temperature on your thermostat?
As a Berkshire plumbing company, we see so many thermostats that are set either too high or too low. So why is 60°C the right temperature and why is it so important?
Why 60°C?
Current UK recommended best practice states that 60 degrees Celsius is the optimum acceptable temperature setting for the thermostat on your hot water heater. Heating hard water above approximately 63°C causes lime-scale to build-up (see photos). So when the temperature is set too high, the resulting scale accumulation reduces the efficiency and the working life of the hot water cylinder. This obviously has financial implications for your utility bills, not to mention the cost of replacing the cylinder more frequently.
And, critically, where the temperature is set too low, there is an increased risk of growth of Legionella bacteria, which can lead to very serious health problems, including severe pneumonia!
6 good reasons to set the hot water cylinder thermostat at 60°C!
- Prevent lime-scale build-up
- Prevent Legionella bacteria
- Prevent scalding
- Save money
- Save energy
- Keep noises and rattling to a minimum
Changing the thermostat temperature
The thermostat has a gauge on the outside that can be raised or lowered either manually or using an appropriate tool.
Combination boilers usually have a hot water temperature setting. Standard systems using a hot water cylinder (usually found in the airing cupboard) have a thermostat mounted on the side and this should be preset to 60 degrees.
If there is no thermostat, then the system is older and it is the thermostat in the boiler that will control the hot water temperature. During colder months you may find that if you turn this down low enough for hot water at a moderate temperature, then the radiators may not be warm enough. The solution to this problem would be a system upgrade.
If your water is heated by electric immersion heater – this is fitted to your hot water cylinder as either the only method of heating your hot water, or as a backup to the central heating boiler – it contains an internal thermostat which also controls the temperature of the water, switching the current on and off as required. The temperature should have been set to 60 degrees when it was installed although this is not always the case. If you are unsure of the current settings, ask a qualified plumber to check it for you.
Water cylinder thermostat positioning
The placement of the thermostat on your hot water cylinder is also very important. The recommended position is at a height of between one quarter to one third of the way up from the cylinder base. This correct position ensures adequate hot water for your household needs.
Important: for reasons of safety, please ensure that any changes to your system are carried out by a qualified plumber .
If you would like more information about the points raised in this article, or would like help with any other plumbing, heating and electrical issues or projects, then please call Chez-Vous Property Services to talk to a Berkshire plumber and electrician on 0118 9770215.
It is Very informative blog. I like your blog. Thanks
Fantastic advice. I’ve linked to you from my hot water cylinders blog because I think our customers will like your blog too.
Ew disgusting pics lol
But, overall great advice especially with the costs of running it.
Many thanks for your comment. Glad that you found the article useful. Best wishes from Chez-Vous Property Services.
http://www.ServicesForProperty.co.uk
How does setting it at 60 degrees save energy, surely the hotter it is the more energy it uses?
Many thanks for your question, Michael.
You save energy because the hot water is not overheated.
We explained in our blog (http://www.servicesforproperty.co.uk/blog/2009/02/setting-your-hot-water-cylinder) the reasons why 60°C is the optimum setting for the hot water cylinder thermostat.
And obviously, each degree setting over 60°C will cost money unnecessarily and is a waste of fuel.
Best wishes from Chez-Vous Property Services.
http://www.ServicesForProperty.co.uk
Great site, keep up the good work, my colleagues would love this. I read many blogs on a daily basis, and for the most part people lack substance, but not in this case. I just wanted to make a short comment to say I’m glad I found your blog, I’m gonna bookmark this http://www.servicesforproperty.co.uk web site. Thanks
Many thanks for your comment. Glad that you find our blogs useful.
Best wishes from Chez-Vous Property Services.
http://www.ServicesForProperty.co.uk
The thermostat on our cylinder is set to around 57 degrees but when we warm the water up, we only leave the boiler on for 10 to 15 mins so that the water does not get too hot to touch. Is this ok to do, or should the boiler be left running until the water has reached the temp set on the thermostat? When the boiler is left running for more than half an hour the water is too hot to use (doesn’t scald but is uncomfortable to use for more than a few seconds).
Many thanks for reading our blog and for your question. Some reasons why the hot water is too hot could be:
- Cylinder thermostat is loose – re-position the thermostat and tighten the strap
- Cylinder thermostat fitted over insulation or surface of the hot water cylinder is unclean – check that the cylinder wall is clean so that there is a good thermal contact
- Cylinder thermostat switch/relays burnt out – the electrical circuit needs to be tested and the cylinder thermostat may have to be replaced.
We hope that you find the above useful. It is obviously difficult to diagnose without checking your installation.
If you’re based in the Reading, Wokingham, Bracknell area of Berkshire and want us to come and take a look, please contact us.
Best wishes from Chez-Vous Property Services.
http://www.ServicesForProperty.co.uk
It is nice to hear about this thing. A cylinder thermostat set up with 60 degree would already produce enough warm air that lets you save more energy.
As long as you leave your airing cupboard door opened.