Night Setback, Explained
What is Night Setback? A thermostat with the night setback function will follow the temperature set by the dial during the period that it is programmed to be on, and then automatically reduce the temperature by 4°C when the thermostat is set to be off.
How does this affect my room temperatures?
The information below shows the temperatures that a room will be set to, when using a time clock linked to a room thermostat.
- Time Clock Mode = On. Set Temperature = 21. Temperature Setback By = 0. Target Room Temperature = 21.
- Time Clock Mode = Off. Set Temperature = 21. Temperature Setback By = 4. Target Room Temperature = 17.
This shows that when the time clock mode is set to ‘ON’, the thermostat will call for heat to get the room to 21°C, as per the thermostat dial setting. However, when the time clock mode is set to ‘OFF’, the thermostat will call for enough heat to get the room to 17°C, which is 4°C lower than the set temperature.
Why does this happen?
Standard thermostats without night setback are either on or off according to the time clock controlling the system. Conversely, thermostats with the setback function will follow the temperature set on the dial during the ‘timer on’ period, and will automatically reduce their set temperature by 4°C when the time clock is set to be off. This essentially means that, even though the time clock display says that the system is off, it is in effect set at 17°C, and will therefore call for heat if the room temperature drops below this.
Why is night setback needed?
Night setback protects underfloor heating systems from frost and helps to keep temperatures consistent, although these are not its principal duties. The main advantages are that it helps to improve the energy efficiency of the heating system and improves the response time, which is the time taken to heat the area. The response time of underfloor heating systems is dependent on the amount of heat energy stored in the floor. For that reason, if the room is kept at 3-4°C below the normal set temperature, the time taken to heat up to the set temperature is reduced substantially.
Problem solving
In the unlikley event that you have a problem with your system, please contact us via email on customerservices@wms-uk.com in the first instance including the following details: Name, Address, Postcode, Contact Number, Contact E-mail, Issue(s).