Gas central heating on constant or timer?

crockpot

Hi

A bloke at work was told by heating engineer that it was better, ie cheaper to keep heating on all the time, I had heard this before, but the chap I asked said not!!

I have an old gas central heating boiler (potterton) which I am ashamed to admit I have not had serviced for 10 years!! since we moved in!!

I am into MSE and only put the central heating on when needed, I see no point it having it on in an am when most days we are out at work and school.

So which is cheaper, on all the time in winter I guess,rad`s all have thermos on so could turn them all down?

Thanks

danz0l

i'd like to know this too. We have just recently turned to timed hot water and turning up the central heating when needed (although the latter is only constant at around 20o).

Gorgeous_George

I'm not sure that you will get a conclusive answer on this one.

I have tried both and found that it made little difference.

Leaving the heating on all the time means that your walls and furniture etc., stay warm and the heating can be left at a lower, comfortable temperature.

Put the heating on only when needed and your walls and furniture need to be heated. To get warm, you need it on higher.

People will argue either way and the argments are convincing. As I say, I tried it and found little difference but it was hardly a scientific experiment.

GG

Cardew

looked at from every possible angle it is cheaper to have it on a timer; no question, there should be no debate(but there always is)

This question has been asked on this forum time and again.

Look at the Energy Saving Trust and they are categoric - a timer is cheaper!

Look at the laws of Physics and that proves a timer is cheaper!

If it is cheaper to leave something heated all the time,(because the mistaken theory states it takes more heat to warm from cold) why don't we leave our kettle boiling all the while, or our gas oven switched on all the time. It is exactly the same principle - albeit more extreme.

Timer Timer Timer - always cheaper. Absolutely no argument!(but someone will no doubt have conducted an experiment with his heating bills that proves the laws of thermodynamics are wrong!!!!)

Conor_3

Cardew wrote: »

If it is cheaper to leave something heated all the time,(because the mistaken theory states it takes more heat to warm from cold) why don't we leave our kettle boiling all the while, or our gas oven switched on all the time. It is exactly the same principle - albeit more extreme

Basic laws of physics state that it takes far more energy to heat to warm from cold than it does to heat from warm to slightly warmer. In addition to that, heat rises so for quite a while when the heating comes on, most of the energy is spent heating the volume of air above head height so it takes longer for you to feel any benefit. Don't believe me? When the thermostat clicks off as it gets to temperature, measure the air temperature at the height of the thermostat then measure it at ceiling height. You'll find a noticable difference. Just think of how much time the heating has been running and heating the ceiling as it brings the air temp at lower heights up to the set level every time the timer is set to come back on. With "always on", that period doesn't exist. The only time there's benefits with using the timer is if there are really long periods where the house is unoccupied and heating not required, say a single period of 8-10 hours a day. (that's 8-10 off, not how long you're out the house)

The oven and kettle analogy is broken because of usage patterns but you'll find that in high use situations (restaurants for example), the boiler and the ovens are left running constantly.

SP1

Hi

Try looking at my previous post

Calvin_2k

I work for an energy company and speak to customers everyday who think its cheaper to leave the heating/ immersion heater on all day.

Its not! Get a timer.

Conor_3

Working for an energy company is no indicator of expertise to back up your statement.

In fact it could be inferred that they've misinformed you so you to tell customers this as they've a vested interest in a customer increasing their consumption.

Ken68

You would need to ventilate the place, at some time, anyway.
Little point in running the heating and having the windows open.

Gorgeous_George

Water is pumped around the radiators. If the house is cold, the water returned to the boiler is cool. If the house is warm, the water returning to the boiler is warm. It doesn't cost much to bring warm water to the heating temperature.

I guess it would also depend on how long you want the house warmed.

My parents use E7 radiators. Their home is always warm and costs no more than my GCH home which is on a timer.

GG

tomstickland

Basic laws of physics state that it takes far more energy to heat to warm from cold than it does to heat from warm to slightly warmer. In addition to that, heat rises so for quite a while when the heating comes on, most of the energy is spent heating the volume of air above head height so it takes longer for you to feel any benefit. Don't believe me?

Yes, but what's been keeping the warm things warm all day?

Basic physics says that heat flow is proportional to temperature difference.

If you think you can save energy by already having the house warm then it would be good practice to leave the heating on all the time if you ever go away for a week or two, because then the house will already be quite warm when you get home, thus saving energy in having to heat a house from cold.