Would it really cost more to always keep the heating on?

[HumanBehaviour]

My husband has the habit of turning the heating on for an hour in the morning and an hour in the evening, each time turning the thermastat to 25C. This means that each time we turn the heating on the radiators has to heat a cold house.

Would it really cost that much more to keep the heating on 19C all the time? If it is kept at a constant temperature it will not have to work as hard each time, IYSWIM?

How do you heat your houses?

Ummm - surely you set the thermostat to your minimum comfy temperature. Then you let the thermostat control whether the heating needs to come on. Once the thermostat is set up correctly, it shouldn't need touching at all and the heating will only start to run once the thermostat detects that the house temp has fallen below your preferred comfy temp.

If you have a clever thermostat you can set it up to have different settings day/night and weekday/weekend.

That way your house is always at least comfortable - but the heating only runs occassionally.

Tianc, I know you keep giving me answers, but they are not answers to what I am asking.

piprabbit: Thanks!

I used to work shifts so we thought it would be a good idea to leave the heating on all the time on low. Our bill was £600 MORE for the three winter months. It was nice all the time though

Go read that thread that Tianc linked to at 14:27, the answer to what you are asking is on there!

(and it is that B uses less than A)

Thanks, Bertha!

Do a spreadsheet and read your meter every month. After this winter you'll have an idea how much you use and how much it costs.

FWIW I have mine on 24hrs and about 23 degrees all winter. Costs me £34 a month dd all year round. I don't know if that's cheap or not as its my first house, it's also tiny.

And also that B will not keep OP warm enough during the day, especially when the outdoors temperature drops.

But that's not on her menu of answers.

Tianc, you must have misunderstood me greatly.

I have not forced you to answer anything so I don't understand why you started being a bit rude when I tried to specify what I meant.

Would it get cold during the day under B I would have to turn the heating on one or two times more. In A the heating would need to work harder duringcold days.

I was asking for a general answer to whether it is more energy efficient to keep the heating on thermostat or only turn it on when needed. I have been given a general answer now.

"each time turning the thermastat to 25C."

don't like that bit.

25C is very warm, verging on the hot.

This approach is most often seen in elderly people, or those who are not used to CH, and think they should switch it on and off like an electric fire

It's usually not possible to persuade them they should change.

The approach is rather like having a cake to bake, and turning the oven up to 220 for ten minutes, then off for ten minutes, then back up to 220.

It is more effective and economical to set the thermostat to a comfortable temperature, then use the timer so it comes on a bit before you get out of bed, or come home; and to go off shortly before you go to bed, or go out. Depending on how well insulated your home is, and how long it takes to cool down, this might be half an hour, or not.

Does this answer your question OP?

I think the solution, OP, is to try it this winter your DH's way & next winter your way (constant) and see which one uses more energy: follow your bills closely.

Then come back and tell us the results!

I am pretty sure that we save (a lot) more by only having the heating on sporadically, though, our bills are so much lower than most people's. Good insulation helps, though.

...and ideally you need daily temperature readings, to adjust for possible differences in prevailing conditions one winter to winter next. Ask around and one of your neighbours may be keeping daily records of temperature. I presume this is your first winter in the UK or I'd say you might be able to start my suggested experiment as soon as the Jan-March quarter coming (using last year's data under your DH's preferences as comparison).

I find Swedish buildings quite stuffy if I'm honest, goes with the high amount of insulation & constant indoor temp regime, maybe. I read that British homes are the coldest in Europe, btw, so something to get used to...?

Ooh, actually, you could go ahead & just do my suggested experiment right away, if you have a meter with lots of digits on it, just do it one week to the next and take meter readings weekly.
As long as you have outdoor temp readings to go with it.
So don't need to wait long at all to establish for yourself which regime is better.

Our indoor temp is only set to 15, btw, 19 would make me swelter, is much warmer than outdoor temps most of the British summer.

We have a clever boiler, which allows different temperature settings through the day. Currently it runs at 13.5 degrees overnight and during the day (ie off), 15 degrees at teatime (5-6pm), and 16 degrees in the morning and evening. It is also a more efficient boiler than we had last year (a* vs b rated), but our bills are about 25% lower this autumn, even with the price hike.
Keeping the house from getting too cold is cheaper than timed heating, keeping the house hot is mor expensive as a rule. Find your lowest comfortable temperature, and set the thermostat to it, remembering that it can be cooler at night as you're under a duvet.

Op - if I were you I would set the heating how you like it for say 3 days, take a reading of your meter before and after, then try the other way for another 3 and take further readings.

You can then see how many units you have used. There is really no definitive answer as to what is the cheapest way to heat your home, there are so many factors to consider. The only way to find out is trial and error and take meter readings.

The answer to this depends on the outside temperature and the lagging of the house.

If, for example it's between 19C and 25C outside (unlikely), then the 19C all the time method will cost nothing as the house will never be cold enough for the heating to come on at all, but the 25C twice a day will cost something as it's heating the house a bit twice a day.

If the temperature outside is greater than 25C (highly unlikely), then it makes no difference, either method will use no energy, the heating will not come on at all.

If the temp is colder than 19C, then the insulation of the house becomes relevent to the answer. Whenever the house is above 19C it will lose more heat than it would have done if it had been at 19C and this energy must be replaced next time you bring it up to 25C. So, if it's well enough insulated that the house stays above 19C before the next time the heat comes on then it will definitely cost more to run the heating twice a day. If it dips below 19C before the next burst of heating then it depends how long for, and if the saving in heat loss when it's below 19C is greater than the rise in heat loss when it's higher (the proportion of time above and below 19C matters here - the heat loss slows as the house gets cooler. So the house would need to be below 19C for quite a bit more than half the time (the cooling curve is exponential, not a straight line) between heating bursts before it would cost more to run the heating continuosly. This happens when it's very cold outside and/or the house is very badly insulated.

you are mistaken.

my answer was in response to the original post where the question was twice a day with thermostat at 25C versus 19C continuosly. I don't believe I am mistaken.

However I do see that the OP then changed her question to whether twice a day at 19C or continuous at 19C was cheaper and then the answer then is easy and straightforward: in all cases of outside temperature and house insulation it will be cheaper to run the heating less often rather than continuosly.

We keep ours on all the time.

16 degrees overnight and during the day when we're out.
18 or 19 degrees the rest of the time.

Chartered surveyor friend said leaving it on all the time was the best option. He said 16 degrees all the time. Reason being that walls will retain the heat and boiler won't have to work so hard. It also helps to stop condensation. I'm not really sure what impact it has on your heating bill but it makes for a far more comfortable living environment.

Thought of freezing cold house one minute then boiling hot the next sends shudders down my spine!

that's fair. You are using 16C as your "unoccupied" temperature. For condensation, and frost protection, 12C would do but is a bit chilly.

A lot of the time, when the stat is set to 16C, it will never actually turn the heating on, because the house will not cool that much. especially if it is well insulated. And yes, it does make the house more comfortable. Here it has been 15C outside today, and sunny, so the solar gain has kept the house fairly warm, but we let the heating run after sunset when it got cooler. 15C was warm enough for actively working in the garden and not needing coat or gloves.

16C is warm enough overnight when you are in bed, and is not icy if you get up in the night, and not cold enough to trouble people who have coughs or athsma.

You are saving money because the heating will be off most of the time, except on very cold winters nights and frosty days. It would be expensive for people who like to keep their house up to "occupied" temperature even when it is unoccupied.