Poor control of heating and hot water services is the cause of excessive energy consumption in many schools. In schools with well-controlled systems, heating fuel consumption is typically 15-30% lower. Good control not only saves energy, but also maintains a consistently comfortable environment for building occupants, as well as reducing boiler maintenance costs. A well-controlled system will ensure that the boiler or heater does not operate unless there is a demand; it only provides heat when and where it is required in order to achieve desired temperatures. Therefore, the selection of appropriate controls plays a key part in the overall running costs of a heating or hot water system. The cost benefits of controls should not be underestimated. Upgrading controls on older heating systems, for example, can save over 15% on energy bills when fitting a full set of controls to a system which previously had none.
How often are heating time settings reviewed at your school? Heating needs vary throughout the day so check that the system operating hours match the times when heating is required. Review time settings every month to check that they are correct. Many systems function inefficiently because someone made a short-term adjustment and then forgot about it.
Determine the optimum times for the school heating to come on and turn off each day. The heating timer should be adjusted so that the school reaches optimum temperature as people begin to arrive, and cools down shortly before people leave. You can do this slowly by gradually adjusting the settings over a small period and checking the response and feedback from teachers and pupils. You could record classroom temperatures hourly across the day, and then work out whether the heating needs to come on earlier or later. Remember the recommended temperatures for schools are:
Normal teaching environment - 18°C
Circulation spaces (e.g. corridors) - 15°C
Areas with high levels of activity (e.g. sports halls) - 15°C
Areas with low levels of activity - 21°C
Special needs schools or areas with very young children - 21°C
When heating needs vary throughout the day and week, perhaps because of after school clubs on some days, review your school’s time settings every month to check they match the times when heating is needed. If short-term adjustments are made to your system, don’t forget to change them back. Installing a seven-day timer will allow for different settings for each day of the week, perfect for when the school isn’t in use over the weekend and holidays.
The Carbon Trust provides detailed information on heating controls at https://www.carbontrust.com/media/10361/ctg065_heating_control.pdf