The following was written in 2007, Weather compensation was mandated in Germany in 1985 on all heat generators. It is refined technology.

This is the first of an occasional series by Alec Morrow who is a heating engineer, registered gas installer and director of Integrated Heating Ltd.

Back in the 1960s and 1970s when I was young there were several winter rituals that my family in Suffolk had to observe to keep warm.

This was in the days of no central heating, blasts of cold air from Siberia (where did they go?), frozen water pipes and frozen condensation on the inside of my bedroom window in the morning.

Such a life wasn't at the time considered hard, in fact we were relatively comfortable. Then came central heating, and my life was changed for ever! Siberia became less of a threat than Russia, and the frozen window panes became big puddles of water on the windowsill every morning

Oh what bliss of modern technology! It was heavenly to wake up in the warmth and not to have to run around turning on electric fires, stoke the cosy stove or light a fire.

I look back on those days of innocence with affection for the logic, when if it was cold you would turn on one bar of the fire (1kW), then as it got colder you would turn on two bars (2kW) or may be three (3kW) or even four (4kW).

We would stock up on wood with several wheelbarrows full for the week in mid winter and in spring and autumn less. Of course if it was really cold we put on an extra woolly jumper and an extra blanket on our beds.

Once the heating was installed a series of other questions were raised. Why did you have to have the hot water on to get heating? Why were some rooms difficult to heat? why was there always a draught up the chimney? And why did it have to get so cold in some rooms before the heating turned its self on from the thermostat?

Of course the opposite happened too, sometimes it was too hot, no one told the boiler that it was warmer today than yesterday and the house being poorly insulated still got very cold at night!

Being inquisitive I had the thermostat in pieces in no time only to find it was mis-calibrated, and the scoundrels of the manufacturers had made it too difficult for a 14 year old to adjust - I thought some special tool was needed.

Of course this type of central heating system was all we in this country knew...it was all just the way things were and with cheap energy from the North Sea no one was really bothered by it. Hey, let's turn the heating up a bit, get a bigger radiator or open a window to cool down. Those days have gone now and it is unlikely that they will ever return.

That innocent childhood served me well as a heating engineer. It showed, as all our predecessors knew instinctively, that to maintain a comfortable temperature you need to vary either the amount of heat being released from the heating system (why use two kWs when one kW will do) or the amount of insulation to our bodies (woolly jumpers).

Science and technology has come along way since then and now the variable heat output that we designed ourselves has been taken over by the microprocessor.

But has it really changed so much? We have to have condensing technology to maximise the amount of heat our boilers get from the gas they burn. Building regulations state that the hot water cylinder should be supplied by pumped circulation rather than gravity because its more energy efficient, and we must have thermostatic radiator valves on all but one radiator, where the thermostat is placed, and this is from where the boiler is told to fire or not!

Other European countries, where energy has never been cheap, looked at the whole equation from a different perspective. If, they asked, a room is getting cool then its because it is losing heat. And with Teutonic logic, they deduced that the answer to keeping a house warm was to replace that lost heat.

Not wait until the one room had cooled off so much that a thermostat, which was probably mis-callibrated (and now I know missing a cable) decided to spring into action and turn the whole heating system on again.

These smart guys in Europe concluded from various studies that the way to keep a house comfortable was to keep various parts of it warm, namely the radiators. Instead of turning the heating on and off as measured from one particular place (the thermostat) they would measure the outside temperature and if it was cold turn the boiler up and if it was not so cold turn it down, just like we all used to do running around turning on the electric fires, stoking up the fire or letting it run down to cinders.

To these smart guys in Europe there was an added benefit; gas can be burnt at near 100 per cent efficiency and the temperature of the flue gas dropped considerably (from about 250°c to 25-70°c). This technology has gone down well with our neighbours - 80 per cent of all boilers in Holland have this control logic or are compatible with it.

Ceding control of your central heating system to the outside temperature returns us to the simplicity we loved. Only this time a microprocessor does it for you, but that microprocessor can do more - when heating your hot water, it ramps up the heat output according to the temperature of the hot water in the tank. Why use 25kW when 5kW will do?

What the Europeans had refined was a system called weather compensation, which literally compensated for the outside temperature. Recent studies by Viessmann Ltd  have confirmed that an additional 10-15 per cent of gas usage can be saved with the correct use of weather compensation on their condensing boilers.

This is on top of the 20-30 per cent that you can save by taking out an old cast iron heat exchanger found in so many of our homes, a big reduction in peoples carbon footprint.