Electric heaters are very expensive to use, one at 1kw can cost over 3 euros a day to run constantly. I would switch them all off and make sure the plumbing is drained down and put up with a cold house for a day (or get a neighbour/ friend to put some heating on the day before arrival.
Mark with the cost of electricity and then the tax on tax that they like to charge I bet you are a bit out must be closer to ā¬5 per 24hr day?
Charges also depend on which tariff you are onā¦frankly, without knowing his usage or tariffā¦ we cannot say whether or not he is being overcharged.
Once @Mat_Davies has worked out the annual usage KW and tariffā¦ he can check all the sites which offer comparisonsā¦ and decide if he really is being taken for a rideā¦ or not.
It has been a couple of years since I have submitted a meter reading so next time we are over I will do it.
Hi Mat ā¦ yes, it would be useful for you to know just how much electricity you are usingā¦ especially when the house is emptyā¦
Which implies that your electric heating used 250ā¬, but how much wood do you normally use in that time? Round here wood prices of 55-60ā¬/stere mean that 6 months wood bumer use would be a lot more than 250ā¬.
Heures Creuse for me is 3 am - 8.30 am and 1.30 pm - 4.30 pm. Water heater timed to come on during those hours and washing, dish washing also done during those hours if possible.
Are you sure about your times? I make that 8,5 hours - HC is only for 8. I only point this out in case you are timing something into HP accidentially.
Correction 3.00 - 8.00 am Went from memory. Should have checked. Anyway works for us
Are you sure it works for you? have you calculated the use on the std tariff? On another forum a chap did an excel spread sheet and you would be lucky not to loose money. I want to change back to std.
We are on the standard tariff, decided itās not worth the hassle with gites, pool etc where most power is used during daytime.
Our monthly payments are 210, 18kw triphase
Since I was looking at the bills for various other reasonsā¦
Tariff Bleu - Option Base, 12kVA - Heating+water is a 16kW air source heat pump in a 150m2 property in south Brittany.
2016 rather expensive at 748ā¬ or 62.33ā¬ per month, 2015 had been considerably better at 529ā¬ or 44ā¬ per month on average.
Considering weāre only there 5-6 weeks of the year that is a bit steep to be honest, the difference between the two years is due to the fact that I left the heating on for January and much of Feb 2017 as we had a cold winter last year and I wound up very worried about the system (and the house) freezing, but it was over 200ā¬ for that peace of mind.
Iām not sure how I feel about the air source system. It was installed by the previous owner replacing an oil fired system and on the positive side (now Iāve got to grips with it to a degree) I can see it is in some ways low maintenance, doesnāt need fuel deliveries etc. On the other hand the unit he chose starts to loose efficiency when the air temperature is below 10oC, which is, of course, just when you need it to heat the house. The installation also didnāt involve changing the radiators so the house has 1950ās cast iron ones - which are not the best for this type of system. Between that and the need for hot water the flow temperature has been set at 58oC which further reduces system efficiency - theyāre much better at flow temperatures around 35o so they work well with things like underfloor heating. I might set the flow back to 55o with hot water at 50o and see if I can knock a few cents off the bill.
Iāve left the heating on again but this time the system has a room thermostat which I fitted over the summer. Technically it doesnāt need one as the temperatures and heat output are supposed to be set up at installation but it always felt odd not to have one and the system has felt ābetter behavedā since it went in. With the mild winter (so far) this year and the fact that I have been able to set a much lower temperature for the system to keep the house at I am hoping that it wonāt just run continuously for 6 weeks like last year 
Paul, There is nothing wrong with the technology, how itās sold is another matter. Using a heat pumps for rads isnāt a good idea unless you double the rad size to allow for a lower temp output. Heat pumps are better for underfloor heating where the temperature is lower.
Not all heat pumps are created equal, the first ones I saw were in Scandinavia and work down to -10c. There are cheaper versions for warmer climates.
I dislike the comments on a good technology because it was sold and installed badly
Sure, in fact I agree with you completely, and I didnāt actually say the technology is no good - I also pointed out that they are good for underfloor heating systems. As I said the previous owner had the system installed - I just donāt think it was the best choice for the house as things stand. I suspect gas would have been preferable, with a tank placed where the heat pump (and as far as I can tell the oil tank for the previous system) is now, but I canāt really justify replacing it and it is more efficient than electric heating (just not very).
The Canadians have pumps which work well down to -15oC and with reduced efficiency down to -25 or lower but, as installed, this one struggles even above freezing.
The heat output is only above 12kW (probably the minimum for the house size) when the outside temp is above +7oC, by -5o it can only put out about 8kW (mostly from the 6.2kW auxiliary heater) which is too low really. Thankfully we have a hearth so can supplement the heat pump with a good old fashioned log fire.
Itās not just he heat output though - the unaltered old style radiators and need to supply hot water necessitate high flow temperatures. The system COP at 10o air temp and 60o flow is only 2.5, itās down to less than 2 if the air is at 0o. At 35o flow the COP for 10 and 0 degrees would be 4.2 and 3.3 respectively and it would remain above 2 even down to -15 outside.
As I said I could maybe drop the flow to 55oC, that would see the COP above 2 down to -7 outside, I could possibly go a bit lower, 52o would see the COP above 2 down to about -9 and be above 3 when the outside temp is more than +7 - and Brittany does generally have mild winters so not all is bad.
Paul, with your mild winters, what are you actually afraid freezing up? We drain down our water, turn off outside both our side and before the meter and not had a problem. Just a thought that you may reduce your costs?
Good to hear about the Canadian pumps, My first sight in Scandinavia was back in 1985 so no doubt things have improve cold temp wise.
John - you obviously favour the technology, do you have a heat pump system yourself?
For a typical winter thereās probably not much chance of a problem.
However last year we had a cold snap with temps below -10, at that I start to worry about the heat exchanger circulation out to the heat pump. The pipes are heavily lagged and the system is supposed to have a standby/frost protection setting whereby it will run the pump to keep the water circulating if the temperature drops below (I think) 5o. That worked fine winter 2015-2016 but not last year, The problem was that the system wanted to run a defrost cycle (not sure why if only in stand-by), found the buffer cylinder water too cold - not surprising as only in stand by - and that situation persisted until it had tried and failed to do a defrost cycle 5 times whereupon it decided the fault was permanent and shut itself down completely (so no attempt at protecting the heat pump outside from frost).
Thankfully a) I now know how to get into the service menu on the controller and clear the fault and b) the heavy lagging was sufficient to prevent burst pipes in the heat pump outside.
Draining the system is a bit of a pain. The HW system in the house is OK, turn the stop cock off and open the taps. The 300l HW cylinder is in the cellar which is below the lowest tap so it wonāt empty but will stay above freezing in all but the hardest winters. To drain the heating circuit is more complex and a fresh change of water annually will accelerate corrosion (no easy way to get inhibitor into the system, unlike low pressure systems with header tanks). Also the first visit of the year in Feb is usually my wife on her own - I think sheād find refilling the system a bit too much.
The project this year is to get remote access working. Stiebel sell a box of tricks to connect the system to a network but I think mine will be too old, in any case it costs an arm and a leg. There is an optical link on the controller intended to connect to a PC, this has the slight problem that Stiebel no longer sell the interface cable so a bit of amateur electronics will be called for, but hopefully I should be able to get to the point I can control the system over the 'net and just turn it on if weāre likely to get prolonged spells well below zero.
Do you have a friend or neighbour who could help? I have a friend with a nearby holiday home and when he leaves for the winter he switches off the water and drains the system but only switches the central heating off. He keeps an eye on the weather forecasts and when he is worried about a cold spell messages me and I go over and switch the heating on.
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One of the neighbors did very kindly offer to look over the place but, at the time, we were due back in a couple of weeks so there wasnāt much need. I didnāt ask for subsequent periods when the house is empty because I donāt really like to impose - especially the village has quite a high percentage of 2nd homes.
To be honest, reading over my posts itās probably less of a problem than I made it sound. The expense last year should be a one off - given the milder weather and better control of the system it shouldnāt be as high this year and after next year I expect to be able to turn the heating on and off remotely from the UK.
That said I keep my reservations about the suitability of a heat pump as a replacement for a conventional boiler driving traditional radiators and also required to generate domestic hot water and I still think that the previous owner was sold a system too under-powered for the house.
Hi Paul, No I donāt have one now, fortunately a lot of my pool customers do so I get involved that way. Why havenāt I got one? Been waiting for the newer variable speed versions to enter the market at more reasonable cost.
I want to maximise the use so for the pool in spring autumn and via a heat exchanger to underfloor in the winter whenever the pool is not in use.
Would you consider using an antifreeze mix in your system and rather than the unreliable frost setting us a low wattage heat tape (trace heating) reliable low cost alternative to letting things freeze.
Are you good with electronics, a few Raspberry pi circuits on the web for controlling most appliances.
I can manage the electronics without too much of a problem. The interface will almost certainly be a R Pi, with a USB to RS232 board, then a bit of DIY electronics to interface to the optical part of things. There is some limited info kicking around on the data protocol between the original PC software (which is no longer available from Stiebel but I located a copy on the 'net) and the controller so Iāll have a bit of software development to do as well.