Sun, 17 May 2026 01:42:18 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=89038#Comment_89038 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=89038#Comment_89038 Sun, 12 Sep 2010 18:33:39 +0100 topher
You are right, setting up and commissioning is included in the price. Before my last payment in December there will be a final visit to check everything is working correctly.

I am the cause of the problem. I like to know what each parameter means and what is the best value for it to be set to. As I said, Dominique has not installed a Nibe system before, so we are learning together. I am very happy with this situation, but of course if Dominique had been experienced with Nibe, that would have been even better.

Your neighbour had an excellent experience, I think it is partly due to heat pump installation being a well understood and mature technology in Sweden. It is not the same in France and the UK. They are behind Sweden in heat pump installations especially the UK.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90028#Comment_90028 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90028#Comment_90028 Wed, 22 Sep 2010 20:10:44 +0100 topher
There is more heat pump info on this link http://www.francethisway.com/wp/pompe-a-chaleur-reduce-your-heating-bills-at-what-cost/2008/06/comment-page-1/#comment-18455

You may be interested to have a browse, however it is specific to France.

Regards,.............Topher.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90248#Comment_90248 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90248#Comment_90248 Fri, 24 Sep 2010 21:02:14 +0100 Canute
I'm guessing we live in roughly the same part of France and having installed ASHP + UFH in 2007 I've been following your thread with interest and look forward to your first-winter reports to see how the two systems compare in similar climates. Have you been able to tap into the various grants/tax breaks ?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90269#Comment_90269 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90269#Comment_90269 Sat, 25 Sep 2010 09:32:11 +0100 topher
I am southern Vendée. Sadly I have decided to keep paying income tax to the UK, so I did not get the generous French rebate.

It may be difficult for us to compare heating, as I often return to the UK in winter and turn the temperature down. However I will be able to compare with my previous propane (v expensive) consumption.

How do you find the ASHP when it is really cold outside? I expect you have resistance heaters in the ASHP.

Amicalement,.............Topher.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90340#Comment_90340 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90340#Comment_90340 Sun, 26 Sep 2010 21:32:44 +0100 Canute
I'm in S.E.Vienne so our winters have a little more bite and you get a bit more sun, otherwise comparable.

Yes the resistance does kick in when it gets below -5 but the ASHP copes well, internal temps maintain the set 19 degrees (I set the thermostat to read a degree higher but don't tell Mrs. C) and the insulation is far from finished so I expect an improvement in overall performance come the end of the refurb when I'll also have a 10kw woodstove for back-up. The ASHP/UFH in cooling mode is a boon in summer but I'm looking at another way to cool - new thread in pipeline.

I'm a fonctionnaire and my kids were born here - being in the system had its rewards re the rebates.

Bonne continuation

Canute]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90413#Comment_90413 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=90413#Comment_90413 Mon, 27 Sep 2010 13:47:56 +0100 topher
Very interesting. I guess that you are British. A Brit becoming a fonctionnaire, wow! Very remarkable, well done.

I wondered about cooling. I think I could just pump the bore hole ground water at 14 degrees under the floors. But one installer said that I could get condensation and as all the flooring has 'slippery when wet' floor tiles, I did not do it. My underfloor heating was put in about 25 years ago, and there was no control over the pipe spacing. If one pipe is well away from the rest, a condensation line might form on the floor surface. It is something I could add myself later, I would need to have the same glycol concentration in the underfloor circuit as the bore holes. You don't have the problem as you can just cool the floor circuit with the heat pump.

Have you considered switching to TEMPO tariff. Perhaps on the red days you could use the 10 kw wood-stove at full blast, and the thermal inertia from the previous day's under floor heat will help. However EDF can give 5 red days in a row, Mon to Friday, that could be the show stopper. I understand, but can not guarantee that EDF, while reluctant, can be forced to give you the tariff. It is shown on their website = http://bleuciel.edf.com/abonnement-et-contrat/les-prix/les-prix-de-l-electricite/tarif-bleu-47798.html#acc52410. I got 100 euros back in the year I switched to TEMPO.

Amicalement,.............Topher.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91162#Comment_91162 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91162#Comment_91162 Tue, 05 Oct 2010 21:36:53 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91164#Comment_91164 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91164#Comment_91164 Tue, 05 Oct 2010 21:42:14 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91165#Comment_91165 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91165#Comment_91165 Tue, 05 Oct 2010 21:45:06 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91166#Comment_91166 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91166#Comment_91166 Tue, 05 Oct 2010 21:48:15 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91167#Comment_91167 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91167#Comment_91167 Tue, 05 Oct 2010 21:56:56 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91169#Comment_91169 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91169#Comment_91169 Tue, 05 Oct 2010 22:04:19 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91170#Comment_91170 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91170#Comment_91170 Tue, 05 Oct 2010 22:08:24 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91171#Comment_91171 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91171#Comment_91171 Tue, 05 Oct 2010 22:17:37 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91172#Comment_91172 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91172#Comment_91172 Tue, 05 Oct 2010 22:23:42 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91173#Comment_91173 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=91173#Comment_91173 Tue, 05 Oct 2010 22:33:39 +0100 topher https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92432#Comment_92432 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92432#Comment_92432 Sat, 23 Oct 2010 18:02:26 +0100 topher On Wednesday 20 October I installed a Kw/h meter and put the heat pump on. It was the first time it had been used to heat the house. It worked fine and brought the house up to 19 as set on the thermostat. I spent some time trying to understand all the different parameters that could be adjusted. I have a lot more to learn.

Everything was fine until Friday, when I noticed that the pressure in the primary (bore hole) circuit had dropped to about 0.2 bar. Previously it had been solid at about 1.5 bar. I opened the inspection cover where all the bore hole pipes are joined to a manifold. If you look back, you will see the picture before the cover was constructed. There were two small pools of red liquid - the manifold was leaking. I told the installer and he said that it was probably caused by the low temperature on the return side. When the heat pump is running the supply side is 9 to 11 degrees, and the return can be minus 2 degrees. It makes me concerned about the leak security of the manifold. In normal operation the temperature will vary from about +11 to - 2 degrees, and if this change is sufficient to provoke a leak, then is this going to be a continual problem?

I have seen a special manifold designed for this application. It has plastic pipe parts with electric resistance heaters which are used to melt the female socket to the inserted pipe. It would seem to give a much more secure connection. With 20:20 hindsight perhaps I should have insisted on one of these. Any one got information to add? It would be very interesting to hear about your experience.

This Saturday morning the heat pump had shut down by itself. The alarm help screen said that insufficient primary circulation was available to work the heat pump. Last night I could hear slight noise of air in the system. I await the arrival of Dominique on Monday to fix the problem.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92549#Comment_92549 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92549#Comment_92549 Mon, 25 Oct 2010 15:56:22 +0100 topher
Yes it really is unlucky 13. Dominique came today and re-pressurised the primary circuit. It was hard to get the pressure above 1.3 bar. The frequent drips coming from one of the manifolds changed to a small stream. Apparently it is a defect in the brass casting of a 'T' fitting. The frequent temperature changes, +11 to -2 degrees every time the heat pump cycles on and off, causes repeated expansion and contraction and has moved the defect in the casting enough to create a pin hole. Repair coming soon.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92552#Comment_92552 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92552#Comment_92552 Mon, 25 Oct 2010 16:33:49 +0100 DamonHD
What a nuisance. Still, better now than mid-Jan I guess.

Thanks for the warts-n-all reporting. Very useful to know.

Rgds

Damon]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92585#Comment_92585 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92585#Comment_92585 Mon, 25 Oct 2010 22:15:38 +0100 topher
Yes very unlucky, but a most unusual defect. Just one of those things I guess. Fortunately when the house was restored, quite a long time ago now, it was equipped with a 9 KW resistance element to heat the water for the underfloor. In those days it was common for houses to be electrically heated - can you remember night storage heaters? Too young I expect. Well, it still works very well, but it is amazingly expensive to run - just for a few days I hope.

Regards,........Topher.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92588#Comment_92588 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92588#Comment_92588 Mon, 25 Oct 2010 22:34:47 +0100 DamonHD
About 1/3rd of UK domestic electricity is still supplied on an Economy 7 tariff I think, though, so there must be plenty still out there... Or maybe one very very big one? B^>

Rgds

Damon]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92595#Comment_92595 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92595#Comment_92595 Mon, 25 Oct 2010 23:14:34 +0100 SteamyTea
I have storage heaters, love-hate relationship with them.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92602#Comment_92602 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92602#Comment_92602 Tue, 26 Oct 2010 00:05:04 +0100 docmartin why do you have a 3 phase supply? I assume they are not standard for homes in France? Do you have an occupation and/or hobby, e.g. welding, that uses 3 phase equipment?
If I were to install 3 phase in a workshop/ studio for my daughter's architectural glass business, would this mean I would have a choice of more efficient heat pumps or just larger models?
I think that Nibe do heat recovery heat pumps which may be relevant to a workshop with kilns. More research needed!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92610#Comment_92610 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92610#Comment_92610 Tue, 26 Oct 2010 06:56:05 +0100 DamonHD
Rgds

Damon]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92621#Comment_92621 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92621#Comment_92621 Tue, 26 Oct 2010 09:19:02 +0100 topher
I should have thought first. I have been to Goonhilly and can understand why you have night storage heaters. My Mum had one, and had the same relationship with it as you do with yours.


Docmartin,

Most houses here are single phase. I believe the following is the explanation for the three phase. In 1985, when the house was restored, it was calculated (wrongly) that 9 Kw of heating was needed. In France circulation of warm water underfloor has always been popular and fortunately it was installed. Taking 9 Kw from a single phase supply is a large load, three phase is better able to supply such a demand. As it turns out, 9 Kw is not enough. When the external temperature is near zero, as it is now, the inside temperature falls from the value set by the thermostat. The previous owner had a big workshop and some three phase equipment, I expect that he was keen on three phase for his workshop as well as his heating.

If your Daughter has kilns and might also have a heat pump, three phase might be the right choice. I would get expert advice from more than one person. Maybe the excess heat from the kilns can be stored, have a look at this http://www.earth.org.uk/milk-tanker-thermal-store.html from Damon's blog.

Most manufacturer's heat pumps are single phase up to about 12 Kw. A 12 Kw heat pump will take about 3.5 Kw from the supply. Beyond 12 Kw they are all 3 phase. As far as Nibe is concerned, the efficiency measured as COP stays about the same for single phase and three phase. Looking at the catalogue, the best COP (output @ 35 degrees) is 4.44 on a single phase machine of 8 Kw. The worst is 4.12 on a 5 Kw single phase and 17 Kw 3 phase.

Leak on manifold being repaired as I type. Hooray. Regards,..............Topher.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92763#Comment_92763 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=92763#Comment_92763 Wed, 27 Oct 2010 09:00:32 +0100 topher
The leak was caused by a brass adapter. It has an axial crack about 2/3 of its length along the larger female threads . If you look at Pic 10 above, the adapter is between the leftmost elbow and the " T " piece to the right of it. I have it as a souvenir. Dominique says it is a very rare occurrence, but he has seen it before.

The heat pump is back on and working fine. Two items remain -
1. I want to get a better understanding of all the parameters that can be adjusted and tweak the system to its ideal settings.
2. I am concerned that the pump is short cycling. I want to increase the hysteresis so that it runs for longer periods at less frequent intervals.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93362#Comment_93362 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93362#Comment_93362 Tue, 02 Nov 2010 09:14:45 +0000 topher
The short cycling was 5 to 10 minutes running only. This was reducing the life of the compressor so I turned it off. I contacted Nibe UK who were brilliantly helpful.

Apparently I should have a return water temperature sensor about half way up the buffer cylinder. The 200 litre buffer cylinder acts an additional load, if I just had the relatively small amount of water in the underfloor pipes, the heat pump would rapidly reach the set temperature, causing short cycling.

As a temporary fix I strapped a temperature sensor on the return pipe going the heat pump. It works fine and now the heat pump runs for about 30 minutes before shutting down. I await Nibe UK to say if it can be left as a permanent solution, or if I need to fit a tube to the buffer cylinder to take the sensor.

When the pump has been running for some time, the water going into the under floor pipes is around 40 degrees. I think this is too high. My next task is to find out how to reduce this.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93366#Comment_93366 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93366#Comment_93366 Tue, 02 Nov 2010 09:50:15 +0000 orangemannot I dont "think" 40 degrees is too hot for underfloor, been running ours at these sorts of input temps ( & higher) this past 15 years.Probably 50/60 at times ( judged by hand only)
Reason is I deliberataly installed an overthick floor screed so the floor is a giant storage heater into which I dump heat.
I suppose you may be concerned about degregation? of the plastic underfloor pipes?
Cheers
M
PS
I would love 3 phase, blinking expensive over here though.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93389#Comment_93389 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93389#Comment_93389 Tue, 02 Nov 2010 13:09:26 +0000 topher
You are right, I am being conservative with my old underfloor heating. I don't want to give it too much temperature cycling. The old plastic pipes are rated to 60 degrees, and I don't know how long they will last.

The other and probably more important reason is that the heat pump has its highest efficiency or COP at 35 degrees. At 60 degrees it falls to 2.71.

Your idea of having a bigger thermal mass with the thick screed sounds good, except that if the weather warms up, does the house feel too hot? And vice versa, when a sudden cold snap arrives, can the system respond?

The house came with three phase - I did not realise at the time the advantage I was getting

Regards,..............Topher.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93465#Comment_93465 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=6164&Focus=93465#Comment_93465 Wed, 03 Nov 2010 11:29:20 +0000 orangemannot But the underfloor is marginal in the living room because the loop is too long, but then the wood burning stove runs in this room basically 24/7 6 months of the year, and I dont think the radiators have been on in 15 years.
But hey it all works.there is a LOT of thermal mass designed into the construction of the house, which is nominally cubical in shape, to give minimium external wall surface for max internal volume.
PS
After 15 years i really really would need to wire up the various timers/controls/valves/thermostats though.
PPS
To heat 3700 sq ft of 1995 insulation standards house to a constant 18/20 deg centi we were burning 2250 litres of oil annually.............. plus the single wood burning stove in the living room.
Not bad i thought.
But now heating from a gasifing logwood burning boiler, in place of the oil input.
Cheers
Marcus
OOOOPs Sorry better answer your question.
If it is cold I put on a bigger fire, plus run the undefloor & radiators for longer and with the thermal mass the temp will not drop to below 16 deg ( and that only very exceptionally, & with me out working all day) before the extra heat input kicks in and corrects. And since we are mostly sitting in the living room with the Morso stove ......it can pick up prob a 5 deg rise in a half hour ( not measured)
The adolescents (numbers vary) upstairs in the computer room never complain but then the amount of electrical energy & occassional alcohol being consumed negates the need for much external heat.
Cheers]]>