Keeping central heating on all the time?

masonic

Skiduck wrote:

so a hotter room above and adjacent that that room will not do anything?

Am I being trolled? Supposing there was a hot room adjacent, it would be heating the slightly cooler room. But the warmer the slightly cooler room is, the faster it loses heat to its surroundings. This issue can easily be dispensed with by expanding considerations to the whole house.

Skiduck wrote:

no, it will loose heat through radiation the same as a cold room, but if a cold room has an ambient external temperature less than the warm room has, it will loose heat at a lesser rate.

True and true. Radiation is, of course, a very minor component of heat loss. This is not true of conduction and convection.

Skiduck wrote:

I am not saying that leaving it on 24/7 is prudent by any means, but it is possible in some limited cases. You have to consider the radiation, convection and heat losses horizontally.

We seem to be going around in circles. Perhaps you could suggest a scenario in which a house being heated constantly at an average temperature of, say 21 °C, might lose less heat over the course of a time of your choice as compared with the same house starting off at that temperature, which is left to cool down.

Cardew

masonic wrote:

Well at least she came back to set the record straight. Plenty of people wouldn't have bothered. There's no point in dwelling on a mistake, Cardew.

Masonic,
Had Shelly admitted she had made a mistake I would have left it there. However I saw no admission in post #60 of a mistake or even an understanding that she had made a mistake, especially when the closing remarks were:

I'm tired of explaining what I know works for us.....

kat21 I suggest you do the same If they don't want to try it ....

Skiduck

masonic wrote:

Am I being trolled? Supposing there was a hot room adjacent, it would be heating the slightly cooler room. But the warmer the slightly cooler room is, the faster it loses heat to its surroundings. This issue can easily be dispensed with by expanding considerations to the whole house.


True and true. Radiation is, of course, a very minor component of heat loss. Fortunately, the same is true of conduction and convection. Again, this issue can easily be dispensed with by expanding considerations to the whole house.


We seem to be going around in circles. Perhaps you could suggest a scenario in which a house being heated constantly at an average temperature of, say 21 °C, might lose less heat over the course of a time of your choice as compared with the same house starting off at that temperature, which is left to cool down.

:rotfl: no, you are not being trolled, and I will not give you an example of that scenario as I have said before, it will depend on many different and varying factors. We do seem to be going round in circles, my main point is that it can be possible in certain situations, whether they are remote or not is not the issue, but there is a possibility. Again the main factors are ambient temperatures, lifestyles, insulation, size of house,orientation of house and it's layout, occupants... the list is endless and thus will not be considered as advice from anyone in the heating industry - I have not advised this at all, but mereley said it could be achievable in certain limited circumstances.

BTW 21 deg is not a temp I would recommend, turn that baby down a bit and you will use less fuel.

masonic

Skiduck wrote:

I have not advised this at all, but mereley said it could be achievable in certain limited circumstances.

I'm sure you would not . Without a scenario or example, it is just theoretical doubt that the theory does not hold in every case. That's ok. Nobody can consider every scenario. All I can say is that none of the variables I can conceive of has any bearing on the end result.

Skiduck wrote:

BTW 21 deg is not a temp I would recommend, turn that baby down a bit and you will use less fuel.

It might amuse some people at this point to learn that I do not have central heating.

tomstickland

Ah, if you were to install central heating and leave it on all of the time then you'd save money compared to not having it at all. This is because not having it all is the same as having a timer and setting it to off all of the time, and timers are widely known to increase fuel usage.

pom_2

I'm late to the party as usual, but here's my two pennies worth;

A much used phrase on another forum I use is that 'the plural of anecdote does not equal evidence' and this applies here.

Just because your 'test' seems to show an energy saving by having the heating on constantly, it doesn't validate your theory. It is more likely that it shows that your 'test' is not a fair one and you lack understanding of the concepts involved.

Cardew

pom wrote:

I'm late to the party as usual, but here's my two pennies worth;

A much used phrase on another forum I use is that 'the plural of anecdote does not equal evidence' and this applies here.

Just because your 'test' seems to show an energy saving by having the heating on constantly, it doesn't validate your theory. It is more likely that it shows that your 'test' is not a fair one and you lack understanding of the concepts involved.

Nice phrase - hope it isn't copyrighted.

similar to:

"Proof by repeated assertion"

tomstickland

I thought of another question today.

If you were going on holiday for two weeks during the winter, would you leave the heating on "ticking over" whilst you were away? This would have the advantage of keeping the fabric of the house warm all of the time and therefore saving money when arriving back from holiday and wanting to heat the house back up.

Extend the holiday period to a year. Same answer?

Yes, I am being facetious.

I do believe that the exponents of the "on all the time method" have seen a saving, but the explanation as to why is wrong.

IGK

I think it's clear that there are scenarios where 'on 24/7 with low thermostat' uses less energy than 'timed with high thermostat', particularly when the ambient (outside) temperature is not much different to the lower 24/7 thermostat setting.
If the outside temp is, say 12c and the 24/7 thermostat is set to, say 16c, then I could invisage less energy being used in that case than with 12 hours per day at 23c.
What I don't understand is what the point of it is.
Setting the thermostat to a comfortable temperature, and having the timer set such the rooms are brought to that temperature when needed is clearly the most efficient. A shorter time in the morning might mean the house doesn't fully heat up to that temperature, but that might be a good thing, and setting it to turn back on late afternoon so the the house is fully comfortable (say by 8pm for sitting down in front of the TV), means the house is warm when you want it and cooler when you don't.
Blasting the house to hotter-than comfortable for timed periods is pointless too.