Flue height

[nobleplus]

Hi to all
I am replacing the roof on my garage to a pitched roof. Have the boiler in the garage with the flue going straight up through the flat roof. My question is how high can a flue be so i can check if it can just be fitted through the new roof or not. If not guess it may be a replacement boiler but I will still need to check where the flue can go. I have a Kingfisher II open flue gas boiler about 12 years old.
Thanks, Tony

 

[heatingman]

The extra flue parts to bring up to todays standards might make it worth considering a total boiler replacement. Suggest you get a couple of local RGi's to come and have a look.
Twin wall flue pipe is very costly and brands are not interchangeable. Its also a bu**er to get hold off.

 

[nobleplus]

Thanks for the reply. I am not very knowledgable in this area. If I understand what you say it's not just a matter of buying an extension kit and making it higher? The instruction booklet has full fitting instructions but doesn't tell the max height the flue can be (as far as i can see). The builder has also said it depends on your boiler type and basically left it to me to decide. A new condenser boiler is suggested if we replace but this will be expensive and it is a shame as this boiler is still in good working order.

 

[doitall]

Depends on the model, the GCNo would help.

But you should be able to extend it without too many problems in twin wall pipe.

 

[heatingman]

A kingfisher II o/f is well over 12 years old more like 20+ years. Don't let your builder mess about with the flue, he might kill you it's dangerous.

 

[nobleplus]

Thanks for your remarks. GCNo?

 

[nobleplus]

It is a Kingfisher II CF 50 G.C.No 41-601-80 if that helps. Where can I go to get this checked?

 

[doitall]

Was hoping I had the manual, but no joy.

 

[Agile]

The instruction booklet has full fitting instructions but doesn't tell the max height the flue can be (as far as i can see). The builder has also said it depends on your boiler type and basically left it to me to decide.

Why do householders ever listen to building on non-boilding matters like gas boilers?

It should be a very easy job to extend your boiler flue but it needs a gas registered engineer and NEVER a builder!

There is virtually no limit on the height of an open flue because the higher it goes the better the "pull" or dranght.

That said, the limit is reached because of cooling of the flue gases so 3-6m is the usual maximum length for a twin wall flue unless extra insulation is added.

Six weeks ago, someone I know had to get rid of about 7m of twin wall from a Kinfisher and most was only two years old!

Tony