1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Filling in gaps around flu

Discussion in 'Plumbing and Central Heating' started by DIYStuart, 16 Jan 2011.

  1. DIYStuart

    DIYStuart

    Joined:
    27 Oct 2010
    Messages:
    12
    Thanks Received:
    0
    Location:
    Sussex
    Country:
    United Kingdom
    I've finally have a new condensing boiler fitted and all it working well.

    Tiding up the area in preparation for fitting a cupboard round the boiler I noticed that where the flu and drain go through the wall the gap between the brick and the pipe haven't been filled ... just a rubber flange pushed round it. This doesn't seal great (at night you can feel a slight draft round it). The plumber has gone on holiday for a couple of weeks so I thought I'd ask here ...

    1) Can I fill the gap with standard mortar?

    2) Should the flu be angled slightly downwards as it crosses the cavity wall? Anything else that does is supposed to (or have low points in the middle) in order to make sure and dampness runs to the outside wall and not the inside wall.
     
  2. Sponsored Links
  3. morlomanc

    morlomanc

    Joined:
    11 Sep 2007
    Messages:
    63
    Thanks Received:
    7
    Country:
    United Kingdom
    youre rgi should have made good around the flue before the flanges were fitted so to ensure poc cant get back into the room. mortar mix is ok.the flue should be angled falling slightly back towards the boiler to collect the condensation.
     
  4. bengasman

    bengasman

    Joined:
    28 Jan 2005
    Messages:
    34,181
    Thanks Received:
    3,124
    Location:
    London
    Country:
    United Kingdom
    This could well be classed as an Immediately Dangerous defect.
    You should as GSR to send an inspector out to check if the rest is safe. Finishing the job yourself could well void the warrantee. Get a RGI to finish it, and send the bill to the installer.
    Which model do you have?
     
  5. kirkgas

    kirkgas

    Joined:
    26 Dec 2007
    Messages:
    4,851
    Thanks Received:
    463
    Location:
    Lanarkshire
    Country:
    United Kingdom
    a flue with a gap is AR at best, until test results prove otherwise, some boiler MI say the rubber flange is acceptable as a permanent finished seal so we would be better checking which boiler he has before we get GSR in, if the flue requires to be sealed then it can be done by anyone, i appreciate it should be weathered but i think it is an over reaction to call it ID, and may panic the OP unnecessarily
     
  6. bengasman

    bengasman

    Joined:
    28 Jan 2005
    Messages:
    34,181
    Thanks Received:
    3,124
    Location:
    London
    Country:
    United Kingdom
    The fact that the op mentions he can feel wind from outside almost surely means poc come back in. POC inside the house = ID
    If this is typical for quality of the work, I would have definitely have safety concerns.

    An inspection by the GSR is not a condemnation, it is simply a verification that all is safe; that is one of the reasons they are free of charge to the caller irrespective of the outcome.
     
  7. DIYStuart

    DIYStuart

    Joined:
    27 Oct 2010
    Messages:
    12
    Thanks Received:
    0
    Location:
    Sussex
    Country:
    United Kingdom
    Alpha CD18R. We've an existing CO alarm in the room (Kitchen) - so I just checked the batteries weren't flat in this.

    I pushed the plastic flange to make it seal better with the wall (before you could see a 2-3mm gap at the bottom). It *could* be air from the cavity I can feel, I'll get a ladder out and check outside tomorrow to see if there's any sealing on the outside wall.

    For a GSR inspector do you mean http://www.gassaferegister.co.uk/help/nominate_work_for_inspection.aspx ? Waiting 3 months for a inspection to tell me I've an immediate dangerous defect doesn't sound too good.
     
  8. Biggles..

    Biggles..

    Joined:
    19 Feb 2006
    Messages:
    30,074
    Thanks Received:
    9,172
    Country:
    United Kingdom
    Your instructions state that you should have an external rubber seal fitted tightly to the wall,if so this doesnt require sealing round the flue externally.
    Internally there should be another plastic flue seal,if this is fitted the internal doesn't need sealing.
    If either are missing sand/cement,sealant,expanding foam,plaster are all suitable.
     
  9. bengasman

    bengasman

    Joined:
    28 Jan 2005
    Messages:
    34,181
    Thanks Received:
    3,124
    Location:
    London
    Country:
    United Kingdom
  10. Sponsored Links
  11. DIYStuart

    DIYStuart

    Joined:
    27 Oct 2010
    Messages:
    12
    Thanks Received:
    0
    Location:
    Sussex
    Country:
    United Kingdom
    Thanks ... the installer didn't leave the installation instructions - just the operating instructions. I've since found these on the web and have had a read (what's that they say about a little knowledge being dangerous ? :) ).

    There was a rubbery seal on the outside as well .. but I can't see it being overly effective when it's windy as the brick faces have a lot of pattern on them. Pushing the inner seal flush against the wall seems to have stopped the draught.

    I still don't overly trust the seals on there own ... next time I've got some mortar mixed up I'll put some in.


    Thanks

    Stuart
     
  12. Agile

    Agile

    Joined:
    26 Jun 2004
    Messages:
    64,017
    Thanks Received:
    4,591
    Location:
    London
    Country:
    United Kingdom
    Gas Safe do not accept that those rubber seals are adequate and expect the flue to be sealed with mortar on the outside. Thats needed for weather sealing to prevent water getting into the wall anyway.

    Only high temperature expanding foam is acceptable and not liked by G-S anyway.

    The flue outside should be horizontal PROVIDING the inner has a built in angle so that the inner is at an angle to slope back to the boiler. Most are now but not all.

    You seems to have had a careless cowboy job done. Probably done by a one day fitter! Possibly because you did not want to pay him to do a proper job.

    Regardless he has to do it properly if he is G-S registered. I suppose he has not completed the Benchmark Certificate or notified Building Control either ???

    Nevertheless you should give the installer the opportunity to put it right. If he refuses or you have any other concerns then you can call G-S and they can issue a defects notice to him.

    Such a cowboy may well have done other bodges as well! Can you post a photo here showing the pipework under the boiler?

    Tony
     
  13. DIYStuart

    DIYStuart

    Joined:
    27 Oct 2010
    Messages:
    12
    Thanks Received:
    0
    Location:
    Sussex
    Country:
    United Kingdom
    In which case why do Alpha say otherwise? I would have thought that the manufacturers and regulators would be saying the same story (mind you I also wonder how the major DIY stores can get away with selling things like 17th edition consumer units. DIYers going to the bother of doing it right and informing BC and getting it inspected and so forth would know they are way overpriced. The only people I can think would buy them are bodgers who don't realise they shouldn't be messing).

    It was a one day job ... from 8:30am till 6pm but I got 3 estimates .. all were within 5% of each other and all said it would take 1 - 1.5 days depending on how things went. There didn't seem a lot to choose between all the quotes. They all quoted for they sparky mates to come in and do the electrics ... which considering the electrics are relatively simple gave me confidence that they were doing it by the book rather than trying to bodge it.

    He said he's going to do this online and that I'll receive a certificate in the post within a couple of weeks, along with the invoice.

    Sure .. I'll have to send when I get home tonight.


    Thanks
     
  14. PEDANTICVINDICTIVEMAN

    PEDANTICVINDICTIVEMAN

    Joined:
    10 Jul 2004
    Messages:
    12,996
    Thanks Received:
    2,710
    Country:
    United Kingdom
    All gets a bit tricky, what Agile says is probably right, but if MI say different, then thats what were "supposed" to follow, I would always cement flue regardless, as it makes less chance for POC entering the property and the flue coming apart which is even scarier.
     
  15. Biggles..

    Biggles..

    Joined:
    19 Feb 2006
    Messages:
    30,074
    Thanks Received:
    9,172
    Country:
    United Kingdom
    Makes me laugh that an installer that follows the instructions,using all Te correct parts supplied for the sole purpose of sealing the flue can be referred to by you as a cowboy.for your info and as you rightly Know MI's are the rules, what gsr say is irrelevant if the MI's state something different.
    If the seals were decorative they wouldn't be supplied,they're functional items especially where external access cant be gained but you flue from the inside.RTFI don't make stuff up to suit you.

    Occcasionally Tony you should get down from your high horse and remember the basics before spouting off.
     
  16. Biggles..

    Biggles..

    Joined:
    19 Feb 2006
    Messages:
    30,074
    Thanks Received:
    9,172
    Country:
    United Kingdom
    Makes me laugh that an installer that follows the instructions,using all Te correct parts supplied for the sole purpose of sealing the flue can be referred to by you as a cowboy.for your info and as you rightly Know MI's are the rules, what gsr say is irrelevant if the MI's state something different.
    If the seals were decorative they wouldn't be supplied,they're functional items especially where external access cant be gained but you flue from the inside.RTFI don't make stuff up to suit you.

    Occcasionally Tony you should get down from your high horse and remember the basics before spouting off.
     
  17. Nige F

    Nige F

    Joined:
    28 Jun 2005
    Messages:
    21,203
    Thanks Received:
    1,741
    Country:
    United Kingdom
    Yet another Gas Safe installation :rolleyes: . Maybe I SHOULD get registered - then go round making good a bit of brickwork - won`t be the first I done :LOL:
     
Loading...

Share This Page