Boilers

[kaz]

You are correct about the flue... this is where the regulations sit. The problem I have is that resiting the flue to an outside wall would HAVE to be done if a new boiler is needed (if the old one can't be fixed). If this should happen, it would probably be the same amount of hassle / cost to just resite the boiler rather than trying to run a flue to an outside wall. In an ideal situation I would want to put a new boiler in the existing site with the flue remaining in the chimney - this is where the regulations hit me.

 

[kaz]

Lol... if someone asked me to list 5000 topics I'd like to talk about, a boiler would NOT be one of them :?... I'm well out of my depth! This is why I am appreciating the help and suggestions on here so much

 

[Flyfisher]

A lot depends on the type of person you manage to talk to in these situations because yes/no answers are often not very helpful. For example, I can (sort of) undestand that a modern boiler flue cannot (legally) be installed to vent into an existing chimney but what if a chimney liner is installed?

My understanding is that wood stoves cannot have their flue connected directly into a chimney but it's fine with a suitable chimney liner, so I can't understand why a similar thing could not be done with an oil boiler. After all the requirement is to ensure the flue gases are safely expelled so surely a long pipe up the chimney would satisfy this requirement?

Unless, of course, the boiler has a balanced flue. I'm assuming the existing boiler doesn't have a balanced flue but perhaps new ones do?

Sorry I can't be more definite about such things (because I simply don't know) but these are the sort of questions I'd be asking to try to understand all the various options, reasons and regulations.

 

[DJH]

I've been out of plumbing and central heating for many years so please don't take this as gospel but my understanding is that all replacement heating units whether they are gas or oil, have to be a condensing model. I understand that to work properly the flue gases are cooled by incoming air for the combustion to get condensation to occur. It follows that to make all this happen a balanced flue has to be used and balanced flues must terminate outside the dwelling within a certain distance from the unit. These flues can be vertical, horizontal or a mixture of both so it doesn't necessarily mean that the unit itself should be on an outside wall but near one especially for a vertical flue where it can terminate through a single story roof.

Just as an aside don't building regs or Water Board by-laws require that no pipe work should be against an outside wall without being suitably insulated? I remember having to insulate pipework beneath sinks because it was sited under a window on an outside wall.

 

[Flyfisher]

Good point about condensing boilers . . . and you're right that these would be more restrictive in terms of where they can be installed.

Oh dear, let's hope kaz can find someone to repair the existing boiler.

 

[DJH]

I don't really know why the existing boiler has been condemned apart from 'running dry', although I'm sure I've missed something, but assuming that it's an oil-fired pressure jet type, it will be much less costly to buy a replacement pressure jet burner than changing the whole boiler along with the attendant hassle.It's very difficult trying to help diagnose the problem from a distance. Maybe some photos would help? :?:

 

[kaz]

Photos are a bit difficult for me to get because I don't live in that area any more. My son sent me a photo from his phone (he lives nearer), but the quality of the photo is dreadful... you can just about make out a boiler . So here it is... the first fuzzy photo is of the boiler and the second is an old photo I had where I've put a red L where the larder cupboard is, which is where the boiler would have to be moved to in a worse case scenario. The existing boiler cupboard doesn't show up in this photo, but I've popped a red arrow to where it is.

Just waiting for the quotes to come through

 

[DJH]

Thanks Kaz. I'm no expert as I've said and I'm not 'up to speed' as they say but one or two things leap out at me from your picture. Nice kitchen by the way. Anyway firstly that looks like a gas flue pipe that has been used to connect it to the chimney flue. From memory the first few lengths for a boiler like this we used to fit a vitreous enamel flue to dissipate some heat from the appliance.

The other thing is that I suspect your heating engineers are reluctant to fit an appliance in a cupboard that doesn't have a fireproof door and maybe doesn't comply to all those sorts of regulations.

I apologise for putting it so bluntly, and I could be completely wrong.

 

[kaz]

Thank you for taking the time to share your thoughts. I wish I understood all this more. I'll up-date when I have more info.

 

[DJH]

Kaz, just been looking at your pictures again. Isn't the boiler against an outside wall now?

 

[kaz]

No... it's on an inside wall right next to an internal chimney breast (sorry I don't have any more photos, but you can just make out the oven which is set in the recess of an old fireplace). I have put a red L on the larder cupboard door which is where the boiler would have to be moved to so it is against an outside wall. I was expecting to receive a quote today... I'll have to chase!

 

[Lime]

Something to ponder on:

Planning regulations.
http://www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_DOMHEAT.pdf

Assessing the case for a non-condensing boiler.
http://www.planningportal.gov.uk/PpWeb/jsp/redirect.jsp?url=http%3A//www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_CONDBOILER.pdf

 

[kaz]

Thank you for providing the links... I must be losing my marbles... I read these last week and again just now, but there is so much 'grey' that I can't make sense of anything. I read somewhere on the internet that the only real requirement is that the flue is accessable to be viewed for inspection via a hatch a minimum of 1' by 1'.

I'm wondering what the hold up is with my new quote... I'm going to email them.

 

[LadyArowana]

When we renovated our boiler was moved. It had previously been under a window in the kitchen, and it died as I was starting to interview builders for the project. The gas man that came ( I was hoping it could be patched up to last till I did the work ) condemned it immediately, it was generating unhealthy levels of CO ( not conservation officers :lol: ) and the flue was totally non compliant. The kitchen was put into a totally different place and the boiler is now on an outside wall in a cupboard. All signed off 4 years ago. Last time I had it serviced, the chap told me that there was now a requirement to put a probe into the flue outlet to perform some sort of test. Of course the way ours was fitted this wasn't possible, but luckily a small extra cutout on the top of the cupboard was all that was needed.

 

[kaz]

So the access to the flue is just so a test can be performed... then in my case, the poor results will probably mean I'll have to get a new boiler anyway! I wonder how they expect people to be able to immediately afford all this stuff?

The new quote has just come through, but without a break down of costs (they are emailing me that later). Again, they have quoted for a new boiler resiting it to the larder cupboard. The guy said that repairs would be a lengthy diagnostic process that would probably end with me needing a new boiler anyway . Price = £5000.

 

[Zebra]

Wonder if I might jump on the end of this thread to ask a simple boiler question, since the thread may have the attention of those who know.... I was planning to site my boiler so that the flue exits through a wall which is perpendicular to the back door and right next to it. Someone said to me that they thought you couldn't have a flue within a certain distance of a door, is this true? If so it will have right messed up my plans!!

 

[LadyArowana]

I believe you are correct. That was the issue with our old boiler vent, it was much too close to the opening window, and doors count too. IIRC there was talk about something needing to be a metre from something else, but in the end it didn't matter as we moved the whole thing.

 

[Lime]

The minimum distance between a flue and an opening in a dwelling depends on the power consumption of the gas appliance.
See link for details.

http://support.ambirad.co.uk/article.aspx?id=10724

Also definition of exactly where an opening begins:
http://www.google.co.uk/url?sa=t&rct=j&q=gas%20flue%20distances&source=web&cd=4&cad=rja&ved=0CFwQFjAD&url=http%3A%2F%2Fwww.nhbc.co.uk%2FBuilders%2FTechnicaladviceandsupport%2FTechnicalGuidance%2F68%2Ffiledownload%2C37239%2Cen.pdf&ei=hKmyUOObB_KT0QX3kYHwBg&usg=AFQjCNGFSOCiiM2bZgvpDDIXzJXhIf0cGw

 

[Zebra]

Oh Lordy. It's worse than I thought. You can't have a flue within 600mm of an internal or external corner. So where I was going to put the boiler totally won't work anyway, with or without the door.
Oh no. What to do?! There's nowhere else to put the boiler. Perhaps I shan't have one. What's wrong with boiling kettles on the stove to fill the sink anyway?
What do others do to heat water, where there is no gas for example?

 

[agbagb]

Zebra, don't panic just yet! I've just checked my boiler instalation manual (ideal logic combi 30).

"Directly below, above, or alongside an opening window, airvent or other ventilation opening - 300mm

From an internal or external corner 25mm* 300mm to BS5440-1

* Only one reduction down to 25mm is allowable per instalation"

If more than 200mm from eaves, 150mm from drain or soil pipe you might be all right.


So I think it's worth checking the exact spec of the boiler and / or checking with plumber (who might be doing the final conections for "Gas Safe" sign off even if you're doing the rest of the instalation)