I thought it was about time I posted some details of my ongoing system installation. After much posting and reading I settled on a system design some time last autumn (I think). My motivation was the ongoing repairs I had been making to a 25 (ish) year old oil boiler which was in the house when we bought it and was moved from what was the integral garage to what is now the boiler / laundry room. The oil boiler was definitely on its last legs and with the constant threat of the rising price of oil (and sea level) I decided to take a look at what else was on offer. I was looking for an automated boiler which could burn primarily pellets with the option of logs and once I had stumbled upon Navitron it seemed apparent that a number of changes would be necessary to accommodate such a beast. We were also already in the process of purchasing a WBS which luckily due to high demand and a long waiting list could be fitted with a back boiler before delivery. As our old boiler was a combi so first on the list was a thermal store and after much head scratching, measuring and calculator bashing I was apparent that if I was going to fit a thermal store in my loft it would have to be relatively small. It also soon became apparent that unless we were going to extend the mortgage (which we were not) a Navitron store was just the ticket.
So far we had a 4kW WBS (2kW back boiler) a thermal store of undetermined size and a boiler of undetermined spec hmmm this was turning out to be a bit more complicated than first expected. To complicate matters further our site was very restricted meaning we either had to install the boiler in the old boiler location which would mean a small extension or build a boiler house at the front of the property. Our local planners soon put a stop to the latter as in the words of our conservation officer "conserving the character of the village was more important than conserving the environment" this meant no construction beyond the building line so the boiler room extension was the only option.
Next was finding a boiler small enough to fit the space we had...this proved almost impossible until I found the Kostrzewa website. With the help of MGL Biomass (Terrier) we planned how to fit the boiler into the space required and connections to the existing heating system and new DHW thermal store. Another thing that soon became apparent was the inclusion of solar thermal to the system, again with much forum help the system design was completed and the thermal store was speced.
So now we had the following system specs:
15kW Kostrzewa Pellet / Wood / Grain boiler
http://www.kostrzewa.com.pl/en/opis-kotla-5839.html4kW Stovax WBS (2kW to room, 2kW back boiler)
216ltr Navitron thermal store, 2 x 28mm WBS connections, 2 x 22mm heat dump connections, 1 x boiler coil, 1 x solar coil, 1 x DHW coil with TMV
Initially I had intended to install a 30 tube 47mm solar collector this spring but from posts I have recently read / made a 40 tube 58mm collector looks like a possibility, then again I may start with 30 47mm tubes and add to it if I need to.
TOOL TIME!!! I decided from the outset that I would be doing as much as I could myself. The first thing to install was the WBS including an external insulated stainless flue some photos of which follow. The WBS is located in a bit of a corner of the living room which was the corner of a bathroom in the house before we extended it and we decided to install it in a false fireplace to stop it looking "plonked" in the room. My wife also had the idea of installing an LCD TV above it and after a bit of Googling in the subject it became apparent that this would be a bit of a challenge due to the heat. Never one to back down from a challenge I decided "whats the worst that could happen" and devised a cunning plan to keep the TV, DVD, HDD and HTPC from keeling over in the heat.
OK so this photo shows the WBS on its Marble tiled hearth with the 600mm enamel flue connected into the insulated flue. You can also see some of the studwork of the false fireplace going up, the studwork on the left is an extension to the brick "nib" required to give enough width to fit the TV in which would also later double up as DVD storage.
Skip ahead a bit and you can see the plastered section the top along with the MDF cut to house the LCD TV and openings for the DVD storage doors along with a nice bit of Oak for a lintel.
A detail of the 100mm rigid insulation above the WBS to keep the TV cool and additional insulation around the insulated flue.
Fire resistant board above the WBS.
SWEDX 32" CAMO LCD TV with Oak surround in place. The fret work panel above hinges up to access the DVD, HDD and HTPC. I'm sure some people will be gnashing their teeth and wringing their hands but I've had the WBS running full tilt for at least 8 hours non stop on several occasions and not one piece of kit has missed a beat. In fact the HTPC definitely gets hotter in summer (lots of glass in the living room extension) if its left switched on than in winter with the WBS on.
And so on to the thermal store, here it is in the loft all plumbed in. I also did this myself you can see the WBS connections on the left and the boiler and DHW on the right.
The insulation on the top of the integrated F&E tank was initially an issue so I made this lovely rigid insulation "hat".
Which combined with a couple of cylinder jackets from Wickes slowed down the standing losses.
On to the boiler installation first of which was the extension to the boiler room which with help from my dad was completed in time for the boiler installation last October. The flue was installed prior to the boiler arriving, that may sound a bit odd but with lots of careful measuring and AutoCAD it was mm perfect and boiler slid straight onto the flue! Standing on the roof and lifting 2.5m of flue into place was a bit hair raising but I'd done 2m off the top of a ladder for the WBS so I was game! (he who dares Rodney)
Here's the mean green machine in place, the pipework has been insulated since the photo was taken. You can see the pellet hopper and auger feed in the foreground. What you cant see is the door behind the boiler for cleaning access etc. and the door in front of the boiler for cleaning the combustion chamber and loading pellets into the hopper. I was lucky enough to qualify for a locally administered Forestry Commission grant for 40% of the boiler and flue cost, Malcom Lowther (Terrier) installed it for me which took about 3 days for the installation and he stayed to set it up for another 2 days which was all covered by his original quote so I was a happy man.
Has it all been worth it? I think it has we've had one problem with the boiler which was faulty O2 sensor and having run it without I would definitely recommend anyone buying pellet boiler to make sure it has a Lambda sensor. The manufacturers quote 20% fuel saving and I can believe it! Its difficult to judge considering the winter we are having but I'm confident that with solar thermal installed it will be significantly cheaper to run than oil.
Ah but how long will you have to run it to get your money back? I hear you ask, well maybe not people on this forum but I hear it a lot and my answer is always the same "If I'd have fitted another oil boiler what would i have spent the money I'd saved on the installation cost on?" and I think its a reasonable question because I damn well know I wouldn't have saved it!
It definitely requires a lot more user input than an oil / gas boiler but i knew that from the word go. It needs cleaning about once a week due to a solid build up in the feed pipe just below the burner, if its not cleaned the auger shear bolt errr shears!
The boiler is highly automated but allows the user to change just about every parameter which was essential to me. I had to install a 7 day timer with a relay and a 10kohm pot on the thermal store temperature sensor input to the boiler to stop it constantly topping up the thermal store, now I usually just give it a 2-3 hour early evening top up which definitely uses less fuel. In my opinion this was definitely an oversite on the manufacturers part.
I've also built a pellet and wood store on the other side of the house which I will post a photo of later. That's all for now, the solar collector installation is still scheduled for some time in spring (whenever that may be!) I'll post more when I think of it.
Hope you didn't fall asleep half way through that.
