Heating with gas

Not sure if anyone can help or steer me in right direction but would appreciate some idea/s. I have a gas central heating and hot water boiler with radiators with individual thermostat controls. The 1 to 5 type. I have 6kva tariff bleu. And I have a gas fired stove in large living room. Town gas.

I usually keep the house (the rooms I use) at an even keel 24/7 and boost evenings with the stove in living room. This way I can get very toasty quickly and I enjoy being warm. My gut tells me that this is more energy and also cost efficient than alternative of keeping the ch a couple of degrees higher so that the ambient temp in house is warm and cosy all day long. I program down a couple degrees from 12-8am while Iā€™m asleep.

I know I can monitor this w/the charts on EDF myespace but would rather not. Just wondering if anyone could venture an educated guessā€¦?

Stone house as insulated as poss with all windows doors at least double glazed. Itā€™s still a stone house!

Where is the main gas CH thermostat located?

Hi. No separate central thermostat. All individual radiators. Was old system installed prior to my purchase. But controls on boiler to program set temps etc.

We also live in a stone house with central heating and all external walls insulated on the inside. We find the most economical way is to turn down the boiler output water temperature to around 56 deg C, or 60 deg C if it becomes exceptionally cold.
Room thermostats are set appropriately for comfortable temperatures during daytime activities, and then we also supplement with an alternative heat source in the TV room during the evenings if needed.
All pipework that runs through uninhabited areas is double insulated.
Our system turns off about an hour before bedtime, and then comes on again at 8am which we find sufficient for our needs. We donā€™t like the idea of the system running while we are asleep on safety grounds, but that is a personal choice.

Years ago (before children), we had our heating turned off when there was no-one at home. With a new baby, and therefore being up at all hours during the night, we were running our heating 24/7 and were very surprised to discover that we actually used less gas than before. So yes, I do think that the most economic way is to basically do what you are already doing to maintain a fairly even temperature with specific localised supplement as and when needed.

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I agree with @Robert_Hodge
Years ago, in the Allier, we looked at a barn conversion undertaken by a a Dutch family.
Theirs was oil CH with exposed stone walls in an exposed location (no insulation visible) and they had the oil burner on 24/7 but very, very low such that you could grip the radiators without any discomfort.
Their contention was that by doing so, the stone walls acted as a heat sink.
They didnā€™t use very much in the way of oil but the house was always warm.
They contended that switching heating off - perhaps during the night whilst asleep and during the day whilst at work was counter productive and then trying to get it warm again was energy inefficient.

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Thats the issue with thermal mass, great for evening out rises and falls in temperature but ultimately more expensive than a highly insulated box with mechanical ventilation (passivhaus).
Same with underfloor heating has to remain on low so if its hot outside the floor is still warm and you are still paying (unless its from solar) letting the slab cool could mean days to reheat it.
Best source of information is the gas meter but tricky as the thermal mass will stay warm for a considerable time before you can experiment with cycling on an off.

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My house is a large stone house with metre thick walls.
We have gas central heating.
All radiators are fitted with thermostats to give local control.
Last year I monitored my daily gas consumption and experimented with the CH settings.
Like others, I found that the optimum consumption was achieved by leaving the heating on 24x7 set to 19C.

The daily gas readings were obtained from GRDF:
https://monespace.grdf.fr/client/particulier/accueil

I also calculated the radiator requirement for each room using the following:
https://www.diy.com/ideas-advice/calculators/btu-radiator-calculator

I found that several rooms had undersized radiators, and I remedied this by installing an additional radiator in 4 rooms. This lead to a huge improvement in comfort and a reduction in overall consumption.

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Thank you all for confirming my gut feeling! I started out by wondering if the gas stove would use more gas. I didnā€™t follow through the logic that one stove vs multiple radiators plus piping throughout house would obvs use less gas!

I love this stove and had one in my vacation home (A-frame) in New Hampshire in US where I couldnā€™t have a fireplace. It looks like a log burning stove but with ceramic logs, plumbed in to gas here with a telecommand! It can also be lit without electricity which was the main plus in NH due to power cuts. So even with the furnace out, can always have heat.

And back to France, I have noticed that itā€™s not getting that cold in the house here (Dordogne) yet even with rads turned way down low because itā€™s so warm . So thanks again for the advice which I will appreciate all the more as/if it ever turns over to winter. I knew someone on here would be able to help. Great job!

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yes, radiators are balanced with 2 in each of the big rooms one of which (biggest of course!) with exposed stone walls.

Donā€™t actually turn off heating at night, just lower by several degrees. So the requirement isnā€™t to actually ā€˜fire upā€™ the boiler. May be different oil to gaz?

@monti it was more the principal I was referring to as an information thing rather than your specifics.
Sorry if that wasnā€™t clear.

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I appreciate thatā€¦as I do all info! I was just curious about the ā€˜firing upā€™ if there;s any difference between oil and gas. and as I donā€™t turn off anyway, moot point. :slight_smile:

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When we had a gas boiler in UKā€¦ it would "fire up " as and when needed, going into ā€œtickoverā€ mode once the appropriate temps had been reached.

Likewise with our oil boiler here in Franceā€¦

of course, Iā€™m talking about the temperature-setting of the boiler

A great post and insight into your building, clearly you have spent time accumilating the data.
Despite the 60cm thick stone walls in France and ground floor single glazing the extreme roof insulation we fitted makes the house feel warmer than the one in the UK! Next year big improvements to the UK house. It has solid (no cavity ) brick walls too thin to gain much thermal anything, they are internally insulated but this will be doubled as will the underfloor insulation troughout. New double glazing with a proper A std not the rubbish we inherited when we purchased. I expect to insulate around the window openings to reduce thermal bridging.

Yes, it was quite the learning curve renovating a stone house. My 2 houses that I renovated in US were the usual timber frame. Taking back to studs made it easier to insulate both from inside and outside. And of course living in New England (Massachusetts and NH), who didnā€™t insulate these old houses as well as possible! Before double and triple glazing, storm windows and doors went up every autumn and down every spring! But there is always something new to learn. And I have renovated my last (as in finalā€¦) house!

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And Stella - I am always open to learning something new!

Today Iā€™ve had the CH boiler On since 6.30amā€¦ each room in use has its own thermostatically controlled radiator.

Iā€™ve just decided that the main room is getting too warm for me, so Iā€™ve turned down the rads and lowered the boiler temp tooā€¦ letā€™s see how things work out.
OH does literally ā€œsufferā€ in cold temps so I canā€™t be too miserly, but Iā€™m keen to reduce things a bit if I can.

Might not use the logburner today as the wind is frightfully strong outsideā€¦ glad to have an alternative source of heating.

I also have an infrared thermometer and like to check all the walls and windows and around the windows and doors. What a great toy!!!

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Me too, and the thermal imaging camera. In France I ramped up the wood burner to very very hot to heat the building up then outside in the cold to look for heat loss, single glazed windows obviously but upstairs just the tip of the chimney pot which despite being very very hot was a good temperature. Fire was +400C and chimney just over 100C. Good to see no obvious heat loss elswhere.

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