cheapest way to use the heating

[asianmaze]

Hi All

First time here. I've done a search but can't find an answer to this. Does anyone know whether it's gnerally cheaper to :

a)leave the heating on low all day, keeping the house at a constant temperature. E.g. coming on at 10am and turning off at 9pm

b) have the heating set to come on for two periods a day at a higher temperature. e.g. 6am-9am and then 6pm to 9pm.

We have a combi boiler and radiators with thermostatic (right phrase?) valves.

All help appreciated here - thanks.

 

[ChrisR]

b).

The more it's on, the more it's costing, so turn it off when you don't need it.
A programmable thermostat can help you control the times/temperatures closely.
If you don't have a wall thermostat at all, you're ++ wasting energy.

 

[D_Hailsham]

The biggest savings will be made by insulating your house. The Gov't is very keen on this as the savings are continual. All Energy companies, gas and electric, have schemes to provide free or heavily discounted wall and loft insulation.

We had our walls done last year and the difference is noticeable. The heating goes off at 2240 and comes on again at about 0600 (varies automatically according to temperature drop overnight). I have a max/min thermometer next to the wall stat and this has never gone below 19C, even when the outside temperature has dropped to 5-6C. Just shows how much heat is being retained in the house.

You say you have TRVs on the rads, but do you have a wall thermostat as well?
What is the occupancy pattern of your house?

 

[JohnD]

heat loss is proportional to: temperature difference x time

so the more hours you keep the inside of the house hotter than the outside world, and the hotter it is, the more energy you will lose.

so heating it 24 hours a day loses much more heat than heating it 12 hours a day.

Quite separate from this fact, improving your insulation (especially loft, cavity walls and draughproofing) will reduce the base loss.

 

[chaotic]

In line with asianmaze enquiry.
Is there any worth in leaving heating on constant to allow fabric of building to warm through, so that room temp is maintained with minimal fuel use?
Including wall and roof insulation.
As an o.a.p., this has been done by the local council, foc.Which we all pay for through our rates.
Look forward to your comments,
Chaotic.

 

[JohnD]

heat loss is proportional to: temperature difference x time

so the more hours you keep the inside of the house hotter than the outside world, and the hotter it is, the more energy you will lose.

This is still true.

If you are heating the house daily, the fabric will not get very cold. You will do better to set the timer to come on an hour before you get up or come home, and go off an hour before you go to bed. the better insulated it is the less cold it will get between heating periods.

If cost isn't important to you, you can run the heating 24 hours if you want. You can also make up a fire with £10 notes. Neither is efficient or economical.

 

[namsag]

After al lot of research into this topic and lot of time spent working out all the calcs regards what outside temp is and raising it to a comfortable level within the various rooms so i can wear just a t shirt and football shorts all year long.
I found the most cost affective method . Was to wait till the meter had been read and stick a bypass on the next day and when it gets too warm just open a window not forgetting to get the meter in for the next read. kidding

This is a question that causes lots of disagreement because everyone feels the cold /heat in different ways and what is comfortable and cheap to run for one person can be too hot and expensive for others.

Mate with same boiler and size house as mine leaves his on 24/7 all year with the room stat set at ten when he is out or in bed only turning it up to 20 when he is in.
His bills are half mine as i have mine on high several times a day due to the wife and kids banging it up to 25 as a matter of habit as they walk past the stat. and i do still have windows open when heating is on as i like the fresh air as well as heat which obviously does not help
Guess a lot of it is down to the individual which makes it an un answerable question

 

[DursleyDonkey]

This only causes disagreement because some people can't accept that common sense and science trump doing what you like and trying to justify it later (with respect). Whatever your mate does, it doesn’t change the simple facts:
1. The more you turn your CH off, the less gas you will burn
2. The lower you set your thermostat, the less gas you will burn

If you're going to keep the thermostat on low all the time then you'll be wasting gas when you're out and too cold when you're in. Better to heat the place to the temperature you want when you're home; and let it go cold when you're not. If you turn it down to 10 when you're not in then you'll probably find that the temperature never goes that low, so it might as well be switched off. Use the timer and you won't have to turn it up and down manually.

 

[namsag]

So out of interest tell me the science and figures.
Middle of winter up north when say heating on for 2 hours in the morning person goes out till say 6 oclock so no heating for 9 hours and house drops to not far off zero they then turn heating on for 4/5 hours , How long does it take to get the house and fabric of the building to get back up to a reasonable temp and how much gas does it burn with the boiler on full blast for the majority of that time as opposed to merely ticking over all day and not having to be on very long to get house back up to temp .

 

[DursleyDonkey]

heat loss is proportional to: temperature difference x time

 

[namsag]

Ok if that equation is right what freezes quicker a hot glass off water or a cold glass of water

 

[spacethegas]

Ok if that equation is right what freezes quicker a hot glass off water or a cold glass of water

i happen to know the answer.

the hotter it is the faster it will freeze.

 

[DursleyDonkey]

The hot glass has more heat to lose. The temperature will fall faster than the cold glass, but as it has further to fall it will take longer. Time for a cold glass to drop by 2 degrees will be longer than for a hot glass.

The CH will replace the heat lost during the day. If the house is hot all day it will lose more heat than if it's cold for half the day. It doesn't matter if it's "ticking over" for a long period, or "full blast" for a short period, the fact remains that it will have to replace the lost heat. Otherwise you would break the laws of physics. So the cheapest option is to reduce the heat loss. All else being equal, the simplist way to do that is to reduce the temperature differential by turning off the heating and letting the house go cold.

 

[spacethegas]

mpemba effect.

 

[namsag]

Thats who the kiddy was spacegas but its not everytime it all depends on various probables .
Which is much the same about what is the cheapest way to heat a house, There are far to many probables to give a proper answer and the biggest probable is every customer is different and use the house in different ways so what works for one does not work for others.
Donkey simple question can you give me a link to any energy site that will confirm less gas is burnt under these conditions . I have heard both sides of this arguement for 25 years and never been shown proof on either side it is a case of it sounds like it makes sense so it must .
Much the same if you asked a hundred people if a glass of hot water froze quicker than cold one 90% would prob think what a stupid question the cold one of course 5%would think it a trick question and say the hot and the other 5% like me and spacegas would be sad gits and know such trivia