MERGED: Should heating / water be left on?

flea72

im no expert, but i would say that having it on all the time works out cheaper

my main reason for saying this, is that a car does more mpg when cruising on a motorway, compared to doing lots of stop starts in town traffic

JasonW_2

Also the water in the system won't cool so it only has to top up the heat rather than heat it from cold all the time. The boiler firing up a lot wastes fuel in the combustion process so that is the other side of looking at it.

JW

MarkyMarkD

It's definitely NOT more cost-effective to leave your heating on all the time.

If your objective is to keep the house at your chosen temperature, during the hours you need it, then the main determinant of the cost (given a particular combination of boiler and radiators) is how much heat is lost from the house. The rate of heat loss is related to the difference in temperature inside and outside the house. So you will lose less heat if the house is slightly cooler when you are not occupying it/don't require the heating on.

Boilers also operate more efficiently (in general) when they are running continuously, rather than in a stop-start manner (as per previous posts). So it's better for the house to cool slightly, and the boiler to have to work harder to warm the house up again, than to have the boiler ticking over on-off-on-off all the time.


BUT having said all that, if your previous strategy was to have the heating on full pelt, with the radiator valves all permanently open, and to toast the house up to a high temperature, then to turn off the heating and let the temperature run down, that WILL cost more than heating it to a sensible temperature (controlled by TRVs). But it's the TRVs that are the money-saving (and comfort improving) point here, not the leaving the heating on for longer.

Robert5988

MMD is correct - without question!

Jason made the point that

"The boiler firing up a lot wastes fuel in the combustion process so that is the other side of looking at it. "

I would point out that if you leave the heating on all the time the boiler is constantly shutting down and firing up again.

swizzlebabe

So I`m better just to put it on when i need it, and when I know I`ll be in all day etc?
Sorry lost the plot a bit.

JasonW_2

The only exception to the rule is probably when it is really cold and there is risk of freezing pipes etc.. having the heating on low is a small price to pay that your pipes will be OK I would think! I do not personally see the point of having heating on for the sake of it when there is nobody in apart from the above exception. You could time the heating to come at different times of the day ie before you get out of bed, before you get home from work, and possibly at some point through the night in the winter, its a personal thing.

Im having a system installed in a few weeks and am going for a digital programmable room stat so you can set different programs for different days of the week for when the heating will come on and off, but also set the temp... so if I want in on all day when Im at work in winter, I can set the temp to maybe 12oC, and then boost to 22oC an hour before I get in from work for example. Well thats the idea at least.

JW

Cagey

I agree that the heating should NOT be left on all the time , relying on the thermostatic valves to control the temperature.

The heating should at least have a timer to control the times you require the heating. I would also fit a room stat in the room which does not have a thermosatic valve(usually lounge). In this way you get the correct temperatre in the room which you spend most of the time. In theory the thermostatic valves should do all this but who sets them correctly & changes them as the weather changes ?.

[Deleted User]

Switching your immersion heater off for 8 hours each night, rather than leaving it on will save you 17p a year.

Robert5988

jack_pott wrote:

Switching your immersion heater off for 8 hours each night, rather than leaving it on will save you 17p a year.

Exactly 17p a year - not per night?
Could you please give us your figures to prove that statement.

Robert5988

Cagey wrote:

I agree that the heating should NOT be left on all the time , relying on the thermostatic valves to control the temperature.

The heating should at least have a timer to control the times you require the heating. I would also fit a room stat in the room which does not have a thermosatic valve(usually lounge). In this way you get the correct temperatre in the room which you spend most of the time. In theory the thermostatic valves should do all this but who sets them correctly & changes them as the weather changes ?.

Not certain what you mean by the last sentence regarding weather. The thermostatic valves act like any other thermostat in that they sense the temperature in the room in which they are situated and open/close a valve to let hot water flow through 'their' radiator. The weather has no affect on their operation.