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To counteract the cheap Italian red while vanity googling 😉
I'll tell her she's primal.
I have taken photos and will label them up tonight, as the boiler room is pretty tight with everything in it so its not clear.
My insulation in the house isn't great as I mentioned before, but its an ongoing project to improve it. Basically the house has been rebuild over the last 12 months (inside and outside stripped back to stone, and re-render and plastered, new roof, new ceiling, new wiring, new plumbing, every lintel replaced, so pretty much the lot)
One thing I noticed yesterday, is that with everything turned off (heating, and zero hot water drawn) the system burnt around 20kg (may'be a little less, but not much) of pellets and had fired up twice in 12 hours.
Which I am told is normal, however it seems odd that the accumulator can only hold its temperature for ~6 hours without anything drawn off before it needs to re-heating.
Hah! Some useful information!
If we assume you're getting 4kWh/kg out of your wood pellets that's 80kWh just to keep the tank warm for 12h or about 160kWh/day - that's the total daily use of a whole family in a typical household for heating and hot water. No matter how badly insulated the accumulator it isn't going to lose that much heat through the lagging so the problem is the efficiency of getting the energy out of the pellets into the accumulator.
So things to look at:
Are the pellets absolutely dry and burning nicely?
If yes, then either the heat exchanger in the boiler or the heat exchanger in the accumulator is not working very well. The heat has to go somewhere and I suspect it's going up the chimney. I'd check the heat exchanger in the boiler is clean and then check the temperature of the water being circulated is as hot as it should be. If the water being circulated quicly reaches temperature then the problem lies in the accumulator heat exchanger.
Which I am told is normal, however it seems odd that the accumulator can only hold its temperature for ~6 hours without anything drawn off before it needs to re-heating.
That's nuts. I thought most modern thermal stores only dropped a degree or so in 24hours.
Is the accumulator thermo-syphoning somewhere? To the rads maybe?
Or is it just emitting too much heat into the boiler room?
I'd check the heat exchanger in the boiler is clean
on your's thats the two black hand screws on the front, take off plate cover and hoover out any ash/debris on the shelves. Remove the turbulators and give them a brush, then clean the fins with the wire brush on the metal rod you should have received. hoover again.
The hot water to the rads is controlled by two switched valves controlled by thermostats in the house, both of the thermostats are off, and I have confirmed that the valves are shut (the pipes above the valves are cold), so I don't think its siphoning out.
The accumulator, is sat on a concrete floor and the walls are warm to touch in the boiler room so there is a lot of heat in there.
The pellets were burning nicely (fine grey ash), however a flue restrictor has been put in and now the ash is very black, and has some lumps of part burnt pellets in it (not many but a few). The flue draw was very good before the restrictor was put in (chimney flue is around 7M long and lined with a 6" Aluminum flue).
The pellets are Verdo (or Brites), and seem ok the are firm when you squeeze them in your hand and they don't hang around long enough to get damp tbh.
Thanks Stoner, I will try that tonight to see if it helps
however a flue restrictor has been put in and now the ash is very black
the ash shouldnt be very black, should still be mid grey.
I have a sprung air valve on my flue to limit the amount of draw pulling through the appliance. MT ought to be able to check it for you. A 7m flue might well need a restrictor given the height.
definitely more black than grey, used to be grey but hasn't been since the flue restrictor was put in place.
then first check the turbulators/heat exchangers, also if you can get to it the flue outlet from the back of the boiler (soot gathers there).
If thats all clear and not stuffed full of sooty ash, then ask MT to check the restrictor. Is it adjustable or a set diameter?
I am 99% sure its adjustable, it had what looked like a weight on the end of a bit of wire.
sounds similar to mine. I use trial and error on mine - move the weight back and forth until during a good burn the valve is gently sitting slightly open.
With proper tools though your man can check flue gas temp/O2 content and adjust accordingly.
Stoner doesn't yours self clean and regulate fan speeds for optimum combustion?...........
With my spare £20k I employ a monkey to stoke it instead 😉
Were they on special offer then?
Paul - was it Paul B from W/hager who set it up for you?
Yes it was although I never actually met him. Everyone was called Paul except the owner of the installation company who was Ali, recommended by someone on here called 'nonk' who no one admits to knowing.
I am not sure this thread is doing a great job of promoting these boilers.
How do they compare to a decent combi?
Genuine enquiry I need/want to replace an aging vented system, to improve efficiency and get rid of the water tanks. My best option so far seems to be a combi boiler fitted by a local tradesman for about the price of a Kona Rove. Should I be considering other fuels?
How do they compare to a decent combi?
if youre on mains gas, you really shouldnt be considering biomass for the next 10 yrs at least.
Ok ta.
Biomass only makes sense off mains grid.
Heat pumps only make sense with super insulated homes probably with PV
Paul there are 2 Paul B's although only one usually goes on site.
Nice bloke has been very helpful on my installs.
Holy thread resurrection 🙂
I stopped posting, as the installation company started grumbling about internet experts (and what muppets that are) and them having to walk away if I didn't get advice from people who knew what they were talking about ..........
Anyway, I have now sacked them, as it became painfully clear that whilst they could talk a good game, they didn't actually know what they were doing and might have left the system in a dangerous state (240V junction boxes, with bare wires near pressure release valves, electrical components with split casings that you could see bare wires etc).
So after giving them yet more chances I got someone form the Northman group out to look at the system and give me a report so I could move forward with this, and the summary was, good news: they have all the components I need, bad news they are all in completely the wrong place and the whole thing needs reinstalling.
The massive heat loss was apparently due to pumps running between the boiler and accumulator continuously, so that all the pipework was acting like a huge radiator, also they had the flow side of a pump going to an 100L expansion tank, which was hot to touch which was also pissing out heat, this meant that the boiler room sat at ~ 29 degrees constantly (which I was told was 'normal').
Added bonuses were: they fitted a flue restrictor, but jammed it open (when boiler was off it was still open), temperature probes weren't screwed in properly into the accumulator so they read 20 degrees less than the actual tank temp, so they thought the tank was 70->75 degrees, where it was actually 90-95 degrees! and whilst they had fixed a Termomix mixing valve, they hadn't bothered with the temperature sensor and they had split open the casing to jam it open at all times!
and those are just the highlights.
I thought I would reopen this, to thank people for their help as it did at least allow me to ask the right questions which meant that I could work out just how much I was being lied to.
Now I have to decide if I get rid of the system, and claim my money back via Sale of Goods Act and get an oil boiler, or find someone else to finish the install......
Bloody hell, that's shocking.
will pm you.
Wasn't a good day, but it was a relief to have my concerns verified; the bloke from the Northman group felt ashamed for them after looking at it, its that badly done.