What you could do dave is go for a log boiler now and then in the future buy a pellet boiler from city plumbing for around 3k and plumb this in to your existing system.

gert the trade price catalogue from the counter and google nu-way pellet boilers.

hi MaryM,
This is the first time I've replied to anything like this and i'm unsure what i'm doing, however, I've been reading this forum for some time as I'm in the process of installing my own log wood boiler system. I've been researching it for about 5 months now. My initial thoughts regarding the remote boiler house are, "how far away is it?", with a large property like yours, obviously lots of rads, plus domestic hot water requirements the pipe sizing is going to have to be quite hefty. Heat loss from the pipes would be considerable unless you insulate properly,-could be expensive to do the job right?? . Secondly, the ammount of water sloshing around in the pipes between the garage and the house could be huge, this is effectively "dead water", but its still drawing energy from the thermal store, and ultimately the boiler. Thirdly, your circulating pumps will need to be sized accordingly,- more expense? Sorry to sound a bit negative but this "district" type installation won't come cheap if done correctly and methinks you will be shovelling wood into the boiler quite frequently just to keep the store topped up, will the boys be up to it??
mike,

Hi,
The comment regarding the pipe runs related to the proximity and position of the boiler and accumulator, and not splitting them up. Putting both at the end of the pipe run in a shed is not a problem. It’s a pity that in the UK our house designs do not leave space for these things, in Europe it would be in the basement and any lost heat would at least float up towards the house. Make sure your energy cabin is very well insulated.

btw many accumulators generate the DHW at the accumulator, which would be rather a long way in your case. What had you in mind for this – a conventional cylinder at the house end, or some form of hot water station (at the house end) using a plate heat exchanger?

The underground pre-insulated pipe can be very very expensive say £50/m before digging so some here have looked at various home made versions and there were some posts on this recently under the topic of insulated pipe and a link to a great website builditsolar dot com.

Cheers, Mike up North

hi Ed,
I too have gone for a plate heat exchanger in a system I'm about to start. I've been researching it for some time now and I decided that getting rid of the airing cupboard cylinder with its associated loft cold water storage tank and having mains pressure hot and cold water was the way forward. Less pipe runs etc.. Problem was though, in the main, plumbers and plumbers merchants seem to be unaware of this new approach to domestic hot water supply, although the technology is old hat and has been used for years in industry. I got my system from Austria, plus the advice.

mike

Hi all, I'm finding this thread fascinating since I'm hoping to install a log-burning boiler at home within the next couple of months. I have detailed below my plans so far, and I'd be really grateful is anyone could let have their thoughts on my ideas. Am I barking up the right tree, or just barking?

The property is a new build 5-bed house over 3 floors with a total floor area of approx 250m2, and I'll be installing underfloor heating on the ground floor with rads on the two upper floors. The house will be well insulated, so I am hoping to install a boiler of approx 20-25KW. I read somewhere that a good rule of thumb is to divide the total volume of the house (a little under 700m3 in my case) by 34, which gives me a figure around 20kW. I am therefore looking at the Atmos DC22S, DC25S and DC25GS and I received some useful information from kotly.com which suggested that the best price-performance came from the S models rather than the more expensive GS models. Kotly stated that they normally recommend 25kW for a floor area of 250m2, and 30-32kW for 300m2 (ie 1kW per 10m2). I am hoping that our English winters are less severe than in Poland, but since we've got the heating on in our old house at the start of September, I'm starting to have my doubts.

I am also looking to install accumulator tanks, and I have read that Atmos recommend a size of approx 1500-2000l for the DC22 and DC25 models. I wish to supply water for underfloor heating on the ground floor, radiators on the two upper floors, and hot water for washing (DHW). I am considering 2x 750l Dukla tanks without coils (http://kotly.com/product_info.php?cPath=27_29_60&products_id=640) plus a 200 or 300l tank with a DHW coil. The reason for using a small tank with the DHW coil is that I also want to install a gas condensing boiler (about 25-30kW) to provide DHW and heating if the wood boiler is not in use (for example if we run out of wood or if there is a fault on the wood boiler). This would allow us to isolate the two 750l tanks and just heat the small tank plus the UFH and radiators, which would heat up much more quickly and use little gas due to the reduced volume of water.

Finally, I have looked at twin-wall insulated stainless steel flues with an internal diameter of 150mm and external 200mm. If we route the flue through the centre of the house and take it through the roof to finish just above the ridge (as per UK building regulations) this will give us a flue height of approx 6 to 7m. I'd like to use a single-wall pipe from the boiler to the ground floor ceiling so that I can recover some heat from it, and then change to the insulated flue at ceiling height. Does this sound reasonable, or is the only way to determine whether the draught is sufficient to install the flue and measure it?

Mike

I dont know much about flues but on my atmos even twin wall flue gets dang hot.

Mike

Have only had it a few months and have used over summer about 1m cube. Lighting every 4 days roughly. Central heating knocks it right down though and I expect to light every other day and every day when cold. I reckon now it will probably be about 10-14 m cubed over a year. I bought the S rather than GS as cost of set up was more efficient for me money wise than efficiency of burn as cutting the extra wood isnt much of a cost to me. If you are buying in wood then the better efficency may pay off. Kotly explained to me that it was a western european Germany/austria) emissions modification more than an efficency saver.

Thanks Terry, you're quite right about Akvaterm making oval/oblong tanks, including a 1500l tank, but I'm afraid I'd still rather use 2 small tanks than one large one. The extra pipework is only another 2 pipes since the large tanks won't have DHW coils in them.

Thanks also to Adam (adwindrum). I'm surprised how little wood you're using since I'd been rather scared by estimates of around 1m3 per kW per season (ie a 25kW boiler should use 25m3 per year, and a 32kW 32m3 per year). I can get hold of plenty of wood, but storing enough wood to season 25m3 per year was worrying me.

Does anyone have any experience of the Orlan boilers being sold by Kotly (http://kotly.com/product_info.php?products_id=820{6}11)? This appears to be even more efficient than the Atmos (91% vs 81-88% according to Kotly), burns anything from sawdust to logs, and only costs about £250 more. It looks like a no-brainer to me, so I'm just wondering if I've missed anything.

Have folks here had good experiences with Kotly? They certainly seem very helpful and quick to respond, but I am slightly nervous about buying from a non-UK dealer. Has anyone had any warranty issues or any other problems with Kotly? I am building a new house so I can claim back the VAT, does anyone know if there are any problems with claiming back the 22% Polish VAT? Finally, has anyone been able to obtain a grant for fitting a boiler that was supplied by a non-UK dealer, or are the grants strictly tied to UK dealers (I'm hoping to install the boiler myself with help from a local heating engineer)?

Sorry for all the questions, but I'm trying to get all my ducks (and logs) in a row before I commit myself!

Mike

I bought from Kotly and was very impressed with the two young guys who rocked up at 10am on mon as they had said they would a week before. I also got a grant as I am in an AONB, and a woodfuel grant had been available all year and I was the last and only applicant. For a few weeks it looked as though I was going to get their full 5k allowabnce but they decided to only give me 2 as it would have been a joke getting 5! There was no hoops to jump through either except to be available for viewings. I had a heating engineer help to fit, but as it was his first log boiler he charged a much cheaper rate - a trick you may want to use. The installation is simple enough though once you have your head aorund things, although its soooo much easier with someone who has experience of doing these things and knows the tolerances etc of pressure vessels etc etc

If you're happy with that I would go with the Dunster deal, you have the advantage of dealing with one source who seem to be approachable and knowledgeable. The boiler that I bought was about £2000 more expensive from UK dealers, so it was definitely worth doing. Bear in mind that the store with the Dunster offer has only one coil; if you're thinking of including solar you'll need to change the spec.

Yes I agree with Billi. Wessex wood fuel are an even better deal.

hi,everyone.
I've been reading and researching this forum for a while now.I am a heating engineer and hope to install a system
in my own property early next spring .
For anyone thinking of installing a system you will be awash with information about boilers and what they do and dont do.However it is very important to pay attention to the technical side of the information and not the price.
There are great differences in prices in some cases and not so difference in boiler(different casing and badge/name).One example of this is the Froling fhg and the ETA,same boiler but difference in price.Basically these are excellent boilers if you are starting from scratch eg new build, as they allow you to have different zones and more readings of temp at the accum tank.Very expensive though.
The boiler i have almost decided to go for is the ORLAN SUPER 25 KW sold by KOTLY.COM for £1569 and £300 delivery to ireland.This is the same boiler as the one advertised by Dunster ie viegas 25 kw.Different badge.Almost £2000 in the difference.oh forgot to mention,you get a free laddomat 21 valve worth £250 free with the orlan super.SORRY i hope i didnt upset anyone who has just purchased a viegas.
I think Mike has worked this out from his previous correspondance.
This is a good boiler at the right money.

Dunsters June 2008 price for the Vigas 25 was £3040 plus VAT plus delivery. The Vigas including a Laddomat and VAT but not delivery from Dunster comes to £3893 which looks like more than £2000 difference to me when you add on delivery. The Dunster package price saves you £647 on their list prices before VAT & delivery.

If you have some arrangement where you only get charged 5% VAT the difference will be reduced but it still won't be much less than £4000 for the boiler, Laddomat and delivery.

hi peter-guilam
I'm in the process of fitting my own log wood gasification boiler, thermal store, plate heat exchanger etc., at the moment. I'm near Malton in N' Yorkshire, if you're in the area you are welcome to have a look. I decided on a Swedish boiler,and Austrian thermal store and heat exchanger.

regards, mike