High Efficiency boilers are designed to increase efficiency by extracting latent heat from the flue gases that would otherwise escape into the atmosphere. They are at their peak efficiency when the heating system water returning to the boilers is around 50°c.

However it has been traditional in the UK that heating systems are designed to work at 82°C flow and 71°C return, to ensure that the correct output from the radiators to heat the room when the outside temperature is -1 to -3°C. Temperatures do not tend fall this low, allowing the radiator temperature to depreciate at other times.

Improvements in boiler design have meant that many new boilers (particularly those in SEDBUK A class) now modulate in output, but still the temperature from the boiler can be at 82°C flow temperature.

Technological advancements also apply to new intelligent control systems on HE appliances. In conjunction with the right room temperature controller, the intelligent controls ensure the boiler is working in its optimum condensing mode for the majority of the time, generating more heat, and saving money for the homeowner. Only at very low external temperatures does the boiler work at maximum 82°C flow temperatures.

Intelligent control systems help to address cyclical room temperatures, which commonly occur with thermostats that have to be frequently changed up and down to maintain a comfortable level of heat.

This is achieved through a sensor which acts as the eyes and ears of the system transferring information about the room temperature and the rate of room temperature rise and fall; modulating the heat output from the entire boiler by reducing and increasing the flow temperature where necessary. This of course is pleasing to the homeowner who does not have to keep changing the control.

It is apparent that homeowners tend to set the start-up time of their heating systems for a worst case scenario. This can mean the house is too warm on milder days and fuel wastage can occur. The intelligent control system can address this issue. Instead of setting the start-up time as with traditional systems, the control calculates this for the home occupier. This means the user simply sets the time they wish to be warm and the boiler works out what time it needs to turn on to meet the heating needs - early on colder mornings and later on milder mornings.

These developments are something a consumer should embrace rather than fear. The advanced controls are simple devices with an LCD screen - which many homeowners will be familiar with (such as mobile phones, digital watches) and can contain very simple user-friendly menus and functionality.