French central heating systems

February is always the least exciting month in our year. If it's going to be cold, or wet, or both, at some point in the year it is usually in February. As if to prove the point, this week has been too cold for cycling, which means I've been stomping around the house looking grumpy, while Mrs B has been gazing miserably at the garden from the window and wishing digging and weeding were possible. Well, each to our own.

The main excitement we have in February - and it's the same every year - is the lengthy debate we have with our central heating engineers. Mostly this 'debate' consists of them telling me I have a super modern efficient heating system, and me getting irate and saying that 'it's a shame we can't control the temperature then, if it's such a great system'.

But at last I think we have made a breakthrough and I have understood what the problem is that's been getting us all hot and cold for all these years...but to be honest, I've thought that every year since we finished our barn renovation. Read below and feel free to tell me if the heating 'experts' are being serious or just trying to stop me hassling them...

Apparently the way our central heating works (and a lot of other peoples, in France at least) is to monitor the temperature outside, and then to provide the right amount of hot water to the radiators to keep us warm enough inside. This implausible approach to heating works because a separate setting called the 'pente' (the 'slope') is made for the exact type of building being heated, and the level of insulation it has - and because any given building will lose heat at a constant rate. 

Sounds unlikely, but not impossible.

There is a temperature control in the house but all it controls is the maximum temperature before the boiler gets shut down. We can't set different nighttime temperatures - they are controlled by the 'slope', which circulates cooler water during the night rather than circulating equally hot water to reach the lower temperature. More economical apparently, and in truth our heating bills aren't too high.

The reason the problem has taken so long to resolve is that we live in a barn, and the original installer never took the trouble to work out what our "slope" and settings should be, and never bothered to explain how it all worked. To further confuse the matter we use a wood burning stove for a lot of our heating. Hence our temperature has been leaping up and down in what has seemd to be a completely unpredictable fashion.

Meanwhile I have been spending hours and hours every winter prodding at the central heating control in the house trying to warm things up, cool them down, or at least liking to think I was making a difference, while all I was really doing is confusing the whole sytem and frequently tripping the boiler fuse, while being completely unaware of how to actually adjust the system.

Initial signs are promising, and we seem to have had a perfectly controlled temperature for the last couple of days. But just to be sure it's not a coincidence, if anyone knows anything at all about central heating in France I'd love a second opinion about whether this story is plausible or not...

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  1. Johnny Norfolk February 15, 2010 at 10:04 pm

    You know I do not like these things that are supposed to do the thinking for you. I like to either turn it up and down as I want it not what the systenm thinks I want. If its too cold try putting an ice bag on the outside censor than should warm the inside for you.

    In one of my stores the canteen thermostates were sealed units so the staff ( being always cold) worked out the ice bag trick and of course it worked.

    I know very little about french central heating, all i do know with all these things is to keep it simple and make sure you are in control.
    Its been really cold here and Mrs N is doing exactly the same thing as Mrs B wanting to get her hands on the garden, with me in tow to carry out her orders of course.

    Too cold for you to cycle, now that must be cold.

  2. Boris February 15, 2010 at 10:31 pm

    Unfortunately the sensor is at roof level, about three metres up, and pretty hard to reach with an ice pack.
    Actually I did get out on the bike for an hour this afternoon and it was quite pleasant, but yesterday I got about 5km before deciding my fingers might drop off and coming home again. Tomorrow looks promising, but possible snow for wednesday…

  3. Jon in France February 16, 2010 at 2:11 pm

    It is indeed possible, and can be very efficient if properly configured, but the key is in “properly configured.” We have it in one of the gites, which, as it happens, is a convereted barn.

    Is your boiler by any chance made by De Dietrich?

  4. Boris February 16, 2010 at 3:48 pm

    The boiler is made by Chappee.
    Glad to hear its a problem with me being a slow learner and not a problem with the boiler, nothing too surprising there then.

  5. Kenneth February 17, 2010 at 11:42 am

    We’ve lived here (Mayenne) for just over a year. It was freezing cold when we moved in, a nasty shock, and on virtually an emergency basis we had a proper 200 litre De Dietrich ballon installed, hooked up to heures creuses, for hot water. This arrangement seems to be standard issue here. But what I would really like to discuss is wood, as in bois de chauffage, for woodburners. This year we were obliged to buy three cordes of logs cut to 50cm at 150 euros per corde, delivered. That big hit of 450 euros left me thinking about other ways to buy wood in cheaply. This year I am hoping to buy in a white van load of metre-length logs with the help of a French neighbour, and having bought a chainsaw, trim them to 50 cm length and split them myself. With any luck I will avoid trimming off any body parts at the same time. Has anybody else got experience with paying high or low prices for bois de chauffage?

  6. Boris February 17, 2010 at 12:00 pm

    Since a cord is about 3.6 cubic metres (we usually use ‘steres’ rather than cords in France, I think) you are paying about 42 euros per cubic metre. Around here at least that’s a pretty good price for wood that has been cut and split for you, assuming it’s oak or another hard wood. We pay that much for wood that hasn’t yet been cut to 50 cm.
    Ask them the price for uncut / split wood and see how much you will save. My guess is, not that much, and there tends to be a bit of waste when you cut wood yourself – bits that are just too big to split etc. also of course petrol and oil costs etc It also takes quite a while to turn wood into firewood, but it’s good exercise!
    We have done this ourselves many times (mostly when chopping up our own trees, cheapest way of all) but this year we have ready cut wood. Next years woodpile, drying quietly in a corner, is in 1 metre lengths and will need cutting up during the spring.
    A lot of expats (ourselves included) have taken to using chainsaws in France but never had in the UK – you get used to them pretty quickly, but of course a look at the safety advice is a good idea first!)

  7. Jacqui U February 19, 2010 at 12:21 am

    We pay 45€ per stere for oak that has been trimmed and cut to our required length (50 cm) but not debarked. It is delivered to our barn on the back of a tractor and offloaded/stacked (with us helping).
    It is however supplied by a neighbour (therefore cheaper probably)who is officially licensed to go out into the garrigue with his tractor/chainsaw and chop down trees.
    He said we could save ourselves the money if we wanted to go out with him and chop the trees down ourselves – but hubby worked out that it really was not worth the hassle – and the cost of fuel/resharpening of his chainsaw!
    One useful tip: if your woodburner says for example that it can take up to 60cm logs (as ours does) order logs slightly shorter at 50cm because they often come bent and/or cut non-square and will not fit if even fractionally over the max length!

  8. Anna February 21, 2010 at 2:38 am

    We are renovating our country home in Brittany and have decided that we would go for electric radiators… no central heating thinggy.

    Have had enough of the so-called “sophisticated” central heating system (we had ours replaced twice in our town house in a span of 5 years!!)

    My mother in law has the same problem in her home in the UK — she just couldn’t deal with the thermostat control system that leaves her too hot or too cold during the day.

    Long live manually operated heaters!

  9. Chris February 21, 2010 at 10:59 pm

    You’ve found wood at good price, over here in Cantal I paid 56 € per stere for 50 cm oak. And it’s not that dry.

  10. Douglas March 24, 2010 at 3:07 pm

    We can get 3 year old oak around here for as little as 25€ a stere, but he is usually too pissed to remember to deliver, so we end up paying 50€ delivered. It has gone up in price since the renewable energy publicity.

  11. Boris March 24, 2010 at 4:14 pm

    Its spooky how that happens – the government encourage the use of wood, or stoves, or geothermal heating, whatever, and even offer grants to help out, and the prices magically double overnight. Coincidence? I think not! Still 25 euros is a great price unless you have to fell the trees yourself…

  12. Patricia James February 20, 2012 at 5:49 am

    i HAVE A FABULOUS SKI CHALEY IN THE ALPS, EDF ARE A NIGHTEMARE. HAVE HAD 2 POWER FAILURES AS THE LOCAL DEMAND THIS WINTER HAS BEEN SO HIGH? nOW CONSIDERING installing a Kalirel gel filled electric radiator system which is supposed to cut down power usage by 30%
    I have 3 de dietrich water ballons – 6 bedrooms, 6 bathrooms – a lot of power and expensive timber to comabt -20 to combat this winter
    Am upgarding insulation too – bills are shocking

    Does anyone have this Kalirel installed?

    Seeems perfect – remote controlled in every room every minute of the day

    Thank Trish

    Chalet Perdu, les gets France

  13. Boris February 23, 2012 at 4:03 pm

    Never even heard of it Patricia but it sounds like a good idea. We’ve also been adding a bit of insulation in a ‘colder’ room, since the price of oil is rising at an alarming rate extra insulation is starting to look like a bargain

  14. Linda Hovord May 24, 2012 at 1:56 pm

    We would just love it it our central heating system was working at all! Now that June is just around the corner if doesn’t seem so urgent but those dark cold nights will be wish us again soon enough. We’ve been trying hard to find an engineer in our area (Eauze, Gers) but I have failed miserably to date so if anyone has a contact that would be wonderful and much apreciated.

  15. Boris May 24, 2012 at 2:33 pm

    Linda, that’s a bit depressing at the end of May to talk of ‘dark cold nights will be with us soon’!
    Hopefully someone will know a plumber, manwhile I think forums such as angloinfo or totalfrance (might have wrong name!) perhaps have ‘local experts’ that can make useful suggestions.