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    Actually it's a Rayburn 300W. I've just had it installed and it's burning far too hot. Everything is turned down (flue damper fully in, spinwheel screwed down hard) and it's uncontrollable.

    I'm probably going to have to fix this myself as the HETAS registered firm that lined the chimney and installed the Rayburn are unpleasant and useless. After paying for the installation, they now say they want an extra £175 for the certification, and that they are going to lie on the certificate about the flue, and that despite assuring me they have worked many times for Aga prior to the work, now say they have never connected a Rayburn up before!

    I'm probably going to have to fit a draught stabilizer, but after my experiments with the cooker today, I think I'm going to need a big one! Is there a type of chimney cowl that might help? Most of them seem to be designed to prevent downdraughts, not excessive updraughts!

    Any advice would be much appreciated! The HETAS registered firm don't even know what a draught stabilizer is!

    • CommentAuthorskywalker
    • CommentTimeJan 30th 2009
    I would be inclined to get a proper installer in to have a look.

    Have you contacted HETAS & told them your story, Aga or indeed trading standards.

    Have you paid them for the work?

    • CommentAuthorchuckey
    • CommentTimeJan 30th 2009
    I would have thought that the gas going up the chimney is the result of a lot of air being drawn into the fire, causing it to burn fiercely. while you seem to have twiddled some damper, has it actualy closed the air flow down, is there a badly fitting door some where that is allowing air in? or a badly fitted panel?
    Speak to some one at Rayburn for likely faults.
    • CommentAuthorcrusoe
    • CommentTimeJan 30th 2009
    This is a common comment from new appliance owners. Of all kinds.

    Excessive updraught can be one of a number of things, not necessarily the flue 'over-drawing' per se.

    If it IS the flue over-drawing, very few cowls will slow that down as they often act as a venturi the higher the wind gets, exacerbating the problem. Is the air-dilution lever on the flue box open, allowing room-temp air into the flue? (and also thus slowing passage of air thro' the firebox). In some cases, use of a Steinen (field-type) stabilizer with weighted draught flap will help, but I have fitted probably only a dozen since the late 70s so quite rare to need this. And it's ugly.

    Excessive firebox temperature can cause excessive updraught. Once you have a good thick bed of ash in the firebox (don't riddle!) try using large sized wood - slows combustion and lowers firebox temps. Use the lever just inside and below the firebox door (roll pin) to allow overfire air - not so critical then if ash is partially occluding ashpit air supply.

    If these guys ARE HETAS registered, they will be on the official list at the HETAS website. If they aren't experienced with WB flues, esp flexis, get someone who IS to check the installation before you have the first chimney fire or condensate problem. And check the flexi is fitted the right way up (male part of spiral pointing downwards, drain-fashion).

    Eeyore :)

    I chose the installers from the HETAS website. They simply haven't a clue, and have turned out to be complete idiots. I'm trying not to lose my temper with them, until they have given me enough rope to hang them with. The lining is a cast-in-situ refractory conctrete. I know it's not green, but the chimney in question was in such a bad way (it dates from C17), it seemed to solve a lot of structural issues.

    The HETAS registered firm are now telling me that they could give me a certificate for a stainless steel liner!

    In their defence, the flue draws at an incredible rate even when not connected to anything. I don't see how anyone competent (in reality) or competent (through some scam certification scheme) could have expected this. Before the Rayburn was connected, the draw up the flue was extrordinary. This was doubly strange as my house is symmetrical, the other chimney at the other side of the house (only 8m away) doesn't perform that way.

    It definitely is an excessive draw problem. If you are familiar with Rayburns, you will be aware that the "soot box" has a front plate that is easily removed for cleaning. Removing that plate, closing the flue damper, screwing the spin-wheel tight, the cooker sat at a high simmer all day. The stove pipe was stone cold, and putting my hand into the flue through the soot box opening, it felt cold. Closing the soot door (adding no fuel) brings the temperature of the oven to beyond roasting! That's why I don't think a draught stabiliser will work. The HETAS registered firm claim never to have heard of a draught stabiliser before anyway!
    • CommentAuthorcrusoe
    • CommentTimeJan 31st 2009
    Yeah that's the plate I was referrring to - Rayburn call it their air dilution or some such as you use the chrome lever to open the top hinge. It would feel cold as you are feeling room-temperature air - that's dilution in action - and from your comment, it got worse when you closed this plate, so the open plate WAS having some effect. It is a question of degrees - try removing the flue pipe entirely and see how well it draws - ok, I'm joking, but you take my point...the more you remove the source of draught by dilution, by definition the slower the appliance burns.

    The SFAS used to produce a booklet called 'Solving Chimney Problems' which was quite helpful. Google?

    Not surprised that both flues are different, despite their mirror symmetry. That goes with the territory.

    A CICO or NACLE- approved cast-in-situ ductube system is a far superior system to any flexi - and is green in this respect - that if properly installed it will have a lifespan in excess of 60 years (a/c to the BBA, who used to certify this system in the UK, where a flexi system will need 5 or 6 changes during that period, based on empirical replacements we undertake @10-12 years). Both my Clearview stoves have this system.

    Not having heard of a stabilizer does raise questions about their experience. Also, they should be able to certify this system under its own merit. Although a HETAS registration has different components - I am not registered for this sort of lining for example. Try CICO direct, or NACLE for comment.

    The firm I worked for over many years had a division doing just this, and the draughts were always good due to the insulative properties of the material, (usually expanded perlite) giving higher flue temps. In a flue which already drew well, this would accentuate that effect by adding excess temperature to the mix. Hotter gases rise faster.

    Don't underestimate fuel size and ash-clogging of firebox as 'slowing' factors in this equation. Wet wood would also do the trick, but we don't do that. Just be glad it's not got a boiler and connected to an unvented cylinder. :)

    My boiler stove goes out if I turn it down and close the secondary air intakes. Also, if you don't set the fire properly it doesn't take. With the Rayburn, its a case of throw in a match, and run for cover!

    I have been using 6x6 green oak off-cuts (been doing some carpentry) to fuel the Rayburn. The spin wheel is sccrewd tight and the wood burning rayburns now have 3 plates that sit on top of the grate.

    The thermocrete lining (oops, I said it!) process was fairly stressful. The stuff squirted out in a few places, but mostly a nasty creosote emulsion stained everything (including next door's walls - very stressful!).
    • CommentAuthorcrusoe
    • CommentTimeJan 31st 2009
    As I said, we used to often get this problem initially, but it often went away of its own accord, simply because as things got a bit cloggy after a few weeks, or they'd get the wood sorted, use larger logs etc.

    Don Burners, the people who made oil conversions for SF Rayburn/Aga for many years (now taken over by Gazco - div of Stovax, Exeter), used to make a fan-assisted vaporising oil burner for this model Rayburn - at the time it was called the Supreme.

    The reason this bit of anoraky info may be of interest was that provided with the kit was a Steinen stabilizer which fitted INTO the flue box. They also provided a mesh cover, which looked naff but covered the working 'ting-ting' stabilizer, and you put the original flue cover into store in case you ever went back to SF.

    They may still do this, which would provide an answer of sorts, and you wouldn't have to guess how far to open the front plate (stabiliser is weighted/adjustable) ...but it won't be a pretty solution.

    My tuppenth worth...

    • CommentAuthortony
    • CommentTimeJan 31st 2009
    Choke or throttle on the flue? works well if you must burn wood.
    • CommentAuthorCWatters
    • CommentTimeFeb 1st 2009
    I have a wood burning fire insert and that's quite dependant on the size of the air inlet. If we open the ash pan door to get the fire going this provides a letter box size opening and the fire burns incredibly strongly, can't leave it unattended like that because it's possible to get the whole fire and chimney resonating a bit like a pulse jet. Quite scary.
    • CommentAuthormaureen55
    • CommentTimeFeb 2nd 2009
    We inherited a Rayburn when we moved into an old farmhouse. The previous owner also had an electric cooker as the Rayburn had problems like yours and she daren't use it. The only way we could use it was to burn hardwood in large pieces. Softwood burnt too hot and fast. We also fire-roped the doors again with thicker rope to stop draughts coming in round the sides, but it was always tempramental. In the end, we bought a solid fuel AGA (not very green I know) but we burnt a lot of wood on it with no problems apart from having to clean out the flues more often. It never got too hot and we never had problems with excessive draw. As we did nothing to the chimney, the only difference must have been the stove design.
    • CommentAuthorJohnh
    • CommentTimeFeb 2nd 2009
    You've done well to get wood to burn on the Aga maureen. Everyone I've ever spoken to has said not to bother trying to fuel a solid fuel Aga with wood.

    How often did you have to clear out the flueways?

    What types of wood did you use?

    Many thanks,

    The Rayburn engineer has just been. His conclusions are:

    1. Need new ash-pit door
    2. New spinwheel
    3. New firebox door
    4. New top to cooker

    Tom - you mentioned using green oak off-cuts. How green? How long had they been seasoned from the date of cutting? Oak should be air-dried for a minimum 18 months (ideally 2 years) before burning.
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