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Woodpellet boiler woes
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I agree you have to have a working system. Would not the RHI incentive for GSHP pumps be advantageous in the UK, in respect of cost recovery?As Manuel says in Fawlty Towers: " I Know Nothing"0
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The simple answer is I don't know and we aren't prepared to bank on it. We are of gas grid etc so should be eligible, but the delays on information with this sort of thing been considerable and I haven't seen full details because caught up in other stuff.
Its retrospectively applied isn't it? And once the fund is gone its gone? We have lost considerable money (not the boiler cost which is s all fry, but lay out of utility areas were designed for this none functioning system and this is now a real cost in space as well as money)
Our decision now has to be on what we have in our pocket, not what we might get back in RHI/grants whatever. Because we are still only at the beginning of our project and have lost money on the boiler and will lose considerably more than the cost of the boiler on the rectification. (Things like our utility room were built specifically with the dimensions of that boiler considered, as we're the layout of the pipe runs for the massive cylinder, which we had to have somewhere we didn't want it etc)
We'd need bore hole gs we think, having looked at it, and the cost impacts of everything are just too much I think if the support is small or fails to come through for some reason. We cannot rely on any authority to protect the consumer in this field either, it seems, so it feels like caveat emptor totally.0 -
Firstly, apologies for the length of this contribution! :rotfl:
I know this has been going on for quite a while now and the thread has been quiet for a month or so, so you may have moved on with your plan to rip out and replace. However I would just like to ask if that is the cheapest option for you? You have all this kit already sitting there; surely it would be far cheaper to get it to work properly than to throw it away?
I'll say up front, as I do in most of my contributions that I'm not an expert in this field but doing research like many others on here as I look to make a decision on replacing a ridiculous storage heater system in an old (Victorian?) brick built, off mains gas network, 3 bedroom, 3 reception, bathroom and kitchen house (all large rooms).
Here are my thoughts, and ideas of what could have been going on - others may disagree of courseAnd I’ll start by saying that I'm making the assumption the boiler has been correctly sized – without knowing all sorts of details about your building size and heat loss characteristics none of us here are in a position to say otherwise.
There seems to have been confusion at the start of the thread about the "tank" (buffer, accumulator, thermal store are probably more meaningful descriptions) and how they work. Probably your understanding has increased greatly since you started this thread so I'm perhaps telling you what you already know. A 500 litre store I believe you said "The hot water is from a coiled pipe within the tank, as I understand it. So that should give 350 (or 370) litres of hot water". My understanding is that these stores are logically (and sometimes physically with a baffle, depending on the make and model) divided, so in your case what your system design would be saying is that you have a tank/store of 500 litres, of which the top (hotter) 350 litres is meant to provide heat for your hot water, and the bottom (cooler) 150 litres would be there to provide the heat for your central heating. So the store started with 2 coils running inside it, one through the upper part which the mains water travels through to extract heat from the store and emerge as “hot water”, the other coil in the lower part to transfer heat to the central heating circuit. This is where the concept of stratification comes in that was mentioned by a previous contributor, you want higher temperature water to remain at the top so you get efficient heat exchange for DHW and lower temperature water to remain at the bottom so you don’t burn yourself if you touch a radiator. Water circulating excessively within the store is a bad think as it mixes the cooler water with the hotter water so some of these stores have a baffle to restrict water circulation. So, in summary, as I see it, at this point you have 2 bodies of water, one which fills the store and circulates between the store and the boiler, the second is the water that flows through your central heating radiators and through the bottom coil of the store. You could say there is a 3rd body of water which is the mains water that flows through the upper coil and on to your taps – each one is separate from the others and none of them ever mix.
Looking at your post #6 on this thread "The system went in over eight weeks ago And has powered the central heating fine on several occasions, getting progressively better I think, but the hot water side has not yet been adaquate once. One bath has run hot enough, but not hot enough to have water to rinse the hair I had joyously shampoo'd.. " It seems to me the heating wasn't far off and the DHW was the problem. And to me that indicated the problem was that the store was not recovering heat quickly enough after the bath had been run, which I’ll return to later.
You mention in your post #22 "There were two coils originally, but the ch coil was removed in the re-plumb in effort to solve the issue. " Do you mean the coil was physically removed from within the store? And the central heating was still connected to the flow and return openings in the store? This is where my lack of experience comes in as I'm not sure if that is possible but it sounds like what you are saying – ie. you now have one body of water which flows from the boiler, into the store and some flows out of the store through the central heating radiators. It sounds an incredible thing to do but if this is actually what was plumbed then I think it would ruin the working of the store. It would seem to me that the flow of water in and out of the store would undoubtedly cause currents within the store that would destroy the stratification, the cooler water at the bottom mixing with the hotter water at the top of the store with the temperature averaging out across the store. And that average would be lower than the 75 degrees you probably need to get decent hot water out of your taps. It may make the central heating run warmer of course but there would be less hot water or the boiler would have to run longer for the whole store to reach the temperature set in the upper thermostat. Like I say, this might help the central heating heat better but I can’t see how it would help hot water production given that the hot water seemed to be the biggest issue in your original post, which leads us back to a point mentioned earlier…
It seems to me the biggest issue was the volume of DHW you were able to extract from the store. You've already said in your post #10 that the temperature was set at 75/80C which matches the recommendation I received from one manufacturer of a similar sized thermal store I looked at. Although I could ask where on the store that thermostat is located? Given that 350 litres of the stores 500 litres are supposed to be for DHW then I’d think that DHW thermostat would need to be, what, say 3/5ths of the way down? The only other thing that comes to my mind is that the recovery time of the store is too slow. One of the previous contributors, “aelitaman” in post #21 also talked about this. He gave you some calculations that I'm certainly not qualified to argue with that indicated the boiler should be quite capable of producing the heat needed to keep it topped up after running a bath etc. so that just leaves insufficient flow through the store. And to be honest this would seem to provide an answer to both your problems, if the water heated by the boiler isn't flowing through the store quickly enough then the upper part won’t recover quickly enough to provide “plentiful” hot water and also the central heating may be extracting heat from the lower part of the store quicker than it is being replenished so it might not heat the house as well as you would have expected/hoped.
So it’s this area I would concentrate efforts on – why is the store not recovering quickly enough? Is the pump simple not pumping the water round the boiler/store circuit quickly enough? Thinking outside the box, could there be a blockage internal to the boiler restricting flow? Could there be a blockage in the pipework between the boiler and store restricting flow? Is the tank plumbed in correctly? – like “aelitaman” asked. I have to say I'm not convinced about the physics of this 500kg pressing down on the 22mm opening as I think most of that 500kg will be pushing down on the floor but… Here’s a question from me to anyone who has managed to get this far down my contribution. Why would a tank/store ever be plumbed with the input at the bottom? I can’t understand why you would ever want that but maybe someone can enlighten me, it seems completely wrong to be taking the hottest water out of the top to pass through the boiler again? Surely you’d always want to take the cooler water from the bottom (even if there are currents in the store, I'm sure it will still tend to be hotter at the top – heat rises after all). So yes, switch the boiler on then see which pipe gets hot first, the one at the top of the store or the one at the bottom.
Final thought, you say you’re getting through lots of pellets, which is puzzling, what’s happening to the heat? If you’re burning the pellets then the heat has to go somewhere. To me it seems there are only 3 places that energy can go, into the water, radiate from the boiler into the boiler room, or go up the flue. It doesn't seem to be the first because you’re not getting the hot water/heating expected, I'm sure you’d know if it was the second, so maybe it’s the third? I guess if the water isn't circulating quickly enough then the store thermostat and the temperature of the water returning to the boiler will be telling it to fire but the water won’t be moving quickly enough to extract all the energy in the boiler heat exchanger, so the heat goes straight up the flue? Maybe you’re just making a contribution to global warming rather than house warming??
Hope that helps in some way!0 -
Wow, what a great post thank you!
I'm going to show it to my husband before replying.
The only update I have really is that after being awarded a judgement in our favour we had to send in Sherri's and recovered the deposit.
This meant we lost the costs we would have claimed for through court, ( a regrettably large sum, exceeding tha amount recovered) and they didn't recover the wretched thing so we have to bear costs for that.
The reason we decided not to proceed further with claim is that their finances are not looking good. (We have wondered if one arm of the business will cease trading, or reemerge with a different name) and because we made our point and stand both with the company and with the MCS. My husband is a corporate solicitor and still feels we had an excellent case for a considerable sum of money, but we are both realists and nothing is recoverable from an empty pot. That they had the judgement against them is significant, and there is no point being vengeful for the sake of it, which is what we feel further pursuing at this point is all would be achieved.
We are absolutely minded that it is not sufficient to power the house. Although the boiler is sold as a certain wattage others in the industry have told us it is not capable of producing that.
We have three options with it now.
1. Sell for spares and repair on ebay or gift it
2. Scrap it
3. Try and get repaired (it wasn't functional) to provide heating/hot water for somewhere else on our property, for example, our much smaller office building which was to be heated by air pump or keep to use in a building we have plans to build in a few years that's much smaller.
Personally I feel slightly dodgy about keeping it. I don't trust it, not since it had the smoking/fire in it. And I feel having said it doesn't work to try and get it working feels a bit wrong! But if the people won't come and get it we have to do something with it.0 -
lostinrates wrote: »We are absolutely minded that it is not sufficient to power the house. Although the boiler is sold as a certain wattage others in the industry have told us it is not capable of producing that.
I don't think you ever did mention what make and model it is/was, but I thought you'd said elsewhere in the thread other professionals had confirmed the 28kw was sufficient for your needs?lostinrates wrote: »Personally I feel slightly dodgy about keeping it. I don't trust it, not since it had the smoking/fire in it.
Wow, I don't think I saw that part of the story! What happened?lostinrates wrote: »And I feel having said it doesn't work to try and get it working feels a bit wrong! But if the people won't come and get it we have to do something with it.
I think what you've said all along is that the system, as a whole, as it was installed for you, didn't work. No shame in my book if you (or someone else) can actually put it together and get it working properly.:)
I'm not clear about ownership of it though as it sounds like you had just paid (and therefore only recovered) the deposit rather than the full amount? Getting off topic a bit now so you don't need to go down that roadI just thought maybe you could get the sheriff to seize it also if it's still technically an asset of theirs and give it to you as part of your settlement? Only of any interest if you can get it to work of course, and it sounds like they've ruined the store anyway if I understood the coil removal correctly.
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