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  1. Harriet Cooper

    Harriet Cooper New Member


    I am moving house soon and our buyers asked for a gas check last minute. I organised this quickly and had no worries about our gas system.

    We have a Bermuda back boiler in our house and two gas men have said it is 'spilling'. This was tested through using a match in the front fire. We had no idea! Both said the only way to fix it is to get a new flue for around £1000 OR just get a new boiler. Our buyers want us to just fix the back boiler.

    Is a problem with the flue the only explanation for the spilling? Also, if we have the flue replaced is this definitely going to solve the problem?

    Thank you
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

  3. townfanjon

    townfanjon Trusted Plumber GSR

    This is a potential massive problem on a house sale , that gas appliance is categorised as ID (immediately dangerous) it should be capped off.
    Personally I would change the whole back boiler system, too old by far these days.

  4. Atouchofgas

    Atouchofgas Plumber GSR

    TBH it depends if the guys knew where to do the spillage test. A lot of guys nowadays are unfamiliar with the old fire and back boilers. They all have different places where to do these tests, if uncertain I'd get another company to check
  5. Harriet Cooper

    Harriet Cooper New Member

    I think I'm going to get someone else out to check.
    I've been having a read online and have another question.
    Could limited ventilation cause the fire/boiler to 'spill'- due to lack of air circulating the room?
    We have a ventilation panel- however we have a book case about 15cm away from it. I'm just wondering if it's limiting the air supply.

    Thank you
  6. Atouchofgas

    Atouchofgas Plumber GSR

    It's definitely a possibility but the engineers should have followed the correct procedures when do these test which involve opening a window if required ( this determines if extra ventilation is required )
  7. jtsplumbing

    jtsplumbing Plumber GSR

    Testing for spillage is a little hit & miss things can effect how it go's, Check out the size of the vent, is the vent direct to outside, is it clear of any obstructions, did they warm up chimney B4 doing test ? what was the weather like that day ? conditions can effect test, Get them to remove fire front and smoke test flue, see if you can get an older guy that has had experience with open flue appliances.
    • Agree Agree x 3
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  8. Harriet Cooper

    Harriet Cooper New Member

    Thanks for your message.
    The vent needs a good clean so I'm going to do that. I've got another guy coming who is experienced in working with back boilers. He's going to smoke test the flue amongst other things. So hopefully I'll have a clearer understanding of what is wrong.
  9. galaxy_plumbing

    galaxy_plumbing Plumber GSR

    As mentioned. Check flue is pulling first. Heat it up and test. Then you know what needs to be done. Good luck.
  10. oz-plumber

    oz-plumber Plumber

    Make sure he runs it for 10 minutes before he does the spillage test.

    If he fires it up and does the test straight away you will most probably get spillage.
    Won't go into the detail as why.
    • Like Like x 1
  11. Last Plumber

    Last Plumber Plumber GSR

    A back Boiler should have a lined flue and in my experience, I haven't come across that many with spillage problems to be honest.

    I personally doubt the spillage test has been done correctly. I cannot think of a BBU where you test for spillage through the fire front.

    I recommend you get an Engineer who is experienced in service and repairs of BBU's.
  12. Darren Jackson

    Darren Jackson Plumber GSR

    Last Plumber, I think that it is the fire that is spilling by the sounds of it. But as mentioned there is a specific way to test the spillage that a lot of newer less experienced guys don't know how to perform properly. On my last ACS a younger GSR thought that waving a match around would suffice, he was asked to stop immediately and go home to restudy the correct procedures. Make sure the Mi is available to the engineer when he comes and make sure they do the tests to the Mi's.
  13. Last Plumber

    Last Plumber Plumber GSR

    Hello Darren,
    I know there is a lot of inexperience around these now due to them slowly vanishing, (shame in my opinion but C'est La Vie),
    I know the OP said the fire was spilling. With a lot of BBU's, (as you no doubt know), the spillage test for the fire front is not done on the fire front itself. That's why I think an experienced Engineer needs to look it over. I may be wrong of course and he/she may well have done the job properly.

    Which Fire front is it?
    • Agree Agree x 1
  14. Darren Jackson

    Darren Jackson Plumber GSR

    Morning Shaun, Yes I agree. I too would like to know which fire front is fitted, Maybe the OP will reply with the make and model of the BBU & Fire front fitted or a picture. Most are tested from the side with a length of tube to get to the draft diverter and some have a hole to put the match in, all are different aren't they, which is why the Mi's (manufacturer's Instructions) are so important to make sure the engineer is doing it properly.
    • Agree Agree x 1
  15. Harriet Cooper

    Harriet Cooper New Member

    Thank you everyone for your help.
    I took the vent off and gave it a good clean.
    Another gas man came and have the boiler a clean. He did a smoke test in just the flue-no problems there.
    He let it run for a while, cleaned the fire front (we don't use this) and checked for spillage- no problems again!
    I could have spent thousands on a new boiler when this one is perfectly fine!

    Thanks again for the help
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