Extending a balanced flue on an oil boiler

Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
I'm wondering about putting a car port on the side of the house. It would be open on three sides. The only problem, is that it would cover and area above the existing boiler flue, which comes through the wall. The boiler is an oil-fired Worcester Heatslave and has (what I assume is) a balanced flue.

Is it possible to extend such a flue so that it goes up vertically through the carport roof, please?
 

Attachments

  • 20220908_130854s.jpg
    20220908_130854s.jpg
    261 KB · Views: 29
  • Side view a.jpg
    Side view a.jpg
    89.3 KB · Views: 27
  • Plan view a.jpg
    Plan view a.jpg
    53.2 KB · Views: 21
  • Front view.jpg
    Front view.jpg
    53 KB · Views: 30
Sponsored Links
Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
Download the manufacturers instructions it will give guidance on flues in car port’s
Thanks. I found one online. It just says discharge into carports or narrow passageways is not recommended. It does give a load of flue options (vertical or low-level), but doesn't really say anything about extending an existing low-level flue vertically up the wall for a few metres. There's something about only using 15 degree bends, which makes me think a 90 degree bend added to what I've already got, would be a no-no?
 
Sponsored Links
Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
That's ancient, no chance you'll get any flue for that any more
I feared that. 1995, the boiler was commissioned. Are these flues not relatively standard parts, then? It just looks like a double-skinned round bit of pipe?
 
Joined
2 Oct 2021
Messages
510
Reaction score
219
Location
North Notts/South Yorkshire
Country
United Kingdom
As above its obsolete its well in overtime at 27 years old
If you want the carport new boiler time .
I wouldn't recommend any oil boiler that starts with a W
 
Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
As above its obsolete its well in overtime at 27 years old
If you want the carport new boiler time .
I wouldn't recommend any oil boiler that starts with a W
I think that might put the project on ice then. It's been a good boiler, to be honest. Still works, so I think I'll have to wait until it dies. No gas where we live, so I guess it would have to be another oil one. Are new ones significantly more efficient?
 
Joined
2 Oct 2021
Messages
510
Reaction score
219
Location
North Notts/South Yorkshire
Country
United Kingdom
Yes current condensing oil boilers are more efficient than yours into the 90%s bit less for a combi,.
Could even consider moving the boiler totally and fitting a external model.
Manufacturers warranties extend to 10 years on some models.
 
Joined
28 Oct 2005
Messages
13,758
Reaction score
3,352
Location
Daventry
Country
United Kingdom
I feared that. 1995, the boiler was commissioned. Are these flues not relatively standard parts, then? It just looks like a double-skinned round bit of pipe?
No, modern boiler flues have a plastic exhaust duct, which would get a bit melty if connected to your boiler. The exhaust gases on your boiler are around 250°C. A modern condensing boiler has exhaust gases around 60°C as they recover more heat from the combustion process
 
Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
No, modern boiler flues have a plastic exhaust duct, which would get a bit melty if connected to your boiler. The exhaust gases on your boiler are around 250°C. A modern condensing boiler has exhaust gases around 60°C as they recover more heat from the combustion process
Thanks, but surely there are enough older boilers out there, that need flue work?
 
Joined
28 Oct 2005
Messages
13,758
Reaction score
3,352
Location
Daventry
Country
United Kingdom
Maybe so but as a manufacturer would you rather continue manufacturing a flue for a 30 year old boiler, or stop manufacturing it and thereby hope to sell a whole new boiler and flue kit in this situation? There are no such thing as generic flue systems in the UK, the regs say that only the boiler manufacturer's own flue system may be used.
 
Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
Maybe so but as a manufacturer would you rather continue manufacturing a flue for a 30 year old boiler, or stop manufacturing it and thereby hope to sell a whole new boiler and flue kit in this situation? There are no such thing as generic flue systems in the UK, the regs say that only the boiler manufacturer's own flue system may be used.

Ah! That last bit is interesting. If that's set out in legislation, then it really does put the tin hat on it. We had a hard enough time a few years ago, trying to find an expansion vessel for it!
 
Joined
2 Oct 2021
Messages
510
Reaction score
219
Location
North Notts/South Yorkshire
Country
United Kingdom
No, modern boiler flues have a plastic exhaust duct, which would get a bit melty if connected to your boiler. The exhaust gases on your boiler are around 250°C. A modern condensing boiler has exhaust gases around 60°C as they recover more heat from the combustion process
Both Hounsfield and Grant flue systems are stainless steel
One of several reasons we won't fit oil boilers beginning with a W !
 
Joined
30 Dec 2008
Messages
1,541
Reaction score
205
Location
Cumbria
Country
United Kingdom
Both Hounsfield and Grant flue systems are stainless steel
One of several reasons we won't fit oil boilers beginning with a W !
Mine is stainless! (Well, the bit I can see from outside the house is). But I'm fairly certain the bit coming out of the back of the boiler is metal (I've a feeling it's black painted mild steel, but can't really remember).
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Top