Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 10/08/2014 21:44, John Rumm wrote:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?


Try and download boiler installation manuals. They will tell you the
flue requirements.


--
Michael Chare

In article ,
John Rumm writes:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?

Internal flues (and it might count as that, not being external) now
have to be accessible for checking (e.g. if enclosed, behind removable
panels). How accessible would it be inside an old chimney stack?

That run of flue would probably cost more than the boiler, unless
the boiler can use bog standard muPVC pipework as a flue.

You could do this with my Keston split flue, but there were rules
about placement of the air inlet - it didn't have to be next to the
exhaust, but it couldn't be on opposite of a building or anywhere
where wind could create a pressure differential. Also, a long exhaust
flue needed a separate condensate drain point fitted, not just
running it all back into the boiler.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On 10/08/2014 22:58, Michael Chare wrote:
On 10/08/2014 21:44, John Rumm wrote:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?


Try and download boiler installation manuals. They will tell you the
flue requirements.

Not the kind of question they answer... (I know all the normal rules on
positions and distances from windows, corners etc)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 10/08/2014 23:15, Andrew Gabriel wrote:
In article ,
John Rumm writes:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?

Internal flues (and it might count as that, not being external) now
have to be accessible for checking (e.g. if enclosed, behind removable
panels). How accessible would it be inside an old chimney stack?

That run of flue would probably cost more than the boiler, unless
the boiler can use bog standard muPVC pipework as a flue.

Ah, I think you are over reading the question - I was not suggesting
routing the whole flue up and along the old stack, simply drilling a
core right in one side of the stack and out the other - hence a standard
length flue kit will go horizontally straight through it rather like it
were a 24" thick wall.

You could do this with my Keston split flue, but there were rules
about placement of the air inlet - it didn't have to be next to the
exhaust, but it couldn't be on opposite of a building or anywhere
where wind could create a pressure differential. Also, a long exhaust
flue needed a separate condensate drain point fitted, not just
running it all back into the boiler.

Yup sure...

I was just thinking of normal concentric standard flues here. i.e.
whether it would be worth avoiding the slight extra expense of an elbow
section and a visible run of flue in the kitchen.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 10/08/14 21:44, John Rumm wrote:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?



I know it's a balanced flue, but is it any worse than showing other flue
liners through old stacks?

Can the flue pipes be assembled, locked together and fed into the stack
whilst being certain the joints have not parted in the process? Do
boiler flues need to be supported every x centimetres?

On Monday, August 11, 2014 9:19:22 AM UTC+1, Tim Watts wrote:
On 10/08/14 21:44, John Rumm wrote:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?

I know it's a balanced flue, but is it any worse than showing other flue
liners through old stacks?
Can the flue pipes be assembled, locked together and fed into the stack
whilst being certain the joints have not parted in the process? Do
boiler flues need to be supported every x centimetres?

Bricks, stones etc tend to fall down old chimneys


NT

On 11/08/2014 09:19, Tim Watts wrote:
On 10/08/14 21:44, John Rumm wrote:
Was looking at possible positions where someone could site a new
boiler... There is a nNice space on the wall in the kitchen which would
be ideal (above where the old floorstander boiler is currently fitted).
However there is a partially removed chimney breast on the outside of
the wall that is in the place the flue would normally exit. (its
corbelled out from the wall about 5' off the ground, and then continues
up to a normal chimney stack).

So I said that they would probably need to have an extra extension in to
boiler flue to run half a meter to the side in the kitchen first, before
turning and exiting the wall in the normal way so as to miss the old
chimney stack.

That got me wondering though, although it does not seem "right" I can't
put my finger on any rule for not sticking the normal flue right through
the old stack - its completely unused and only about a foot deep. Can
anyone think of a reason?



I know it's a balanced flue, but is it any worse than showing other flue
liners through old stacks?

Can the flue pipes be assembled, locked together and fed into the stack
whilst being certain the joints have not parted in the process? Do
boiler flues need to be supported every x centimetres?

Everyone seems to be misreading this... ;-)

Cross sectional view:

#C|
#C|
#C|
#C|
/====F
BB#C|
BB#C|
BB#/
BB#
#
#
#
K W O

B = boiler, F = boiler Flue, C = disused chimney, K = In kitchen,
W = Wall, O = Outside

There would be no joins - the chimney is only 12" thick and the flue
would go across it, not up it.

(this is only an academic discussion, since in reality a quick dog leg
in the kitchen will let the new flue miss the chimney and that ought to
cause less confusion - which is generally a good thing)

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 11/08/14 11:36, John Rumm wrote:

Everyone seems to be misreading this... ;-)



Cross sectional view:

#C|
#C|
#C|
#C|
/====F
BB#C|
BB#C|
BB#/
BB#
#
#
#
K W O

B = boiler, F = boiler Flue, C = disused chimney, K = In kitchen,
W = Wall, O = Outside

There would be no joins - the chimney is only 12" thick and the flue
would go across it, not up it.

(this is only an academic discussion, since in reality a quick dog leg
in the kitchen will let the new flue miss the chimney and that ought to
cause less confusion - which is generally a good thing)


I cannot see *anything* logically wrong with that - especially as you
could clearly get an unjointed flue section right through the chimney so
no hidden joints.

The next logical option would be to bore a bigger hole right through
then line that with a big metal sleeve then pass the flue through,
sealing on the outside, bit like passing a gas pipe through a cavity wall.

Actually when you think about it, what's the difference between the
above and passing a flue through a cavity wall?

Cheers

Tim

On 11/08/2014 12:46, Tim Watts wrote:
On 11/08/14 11:36, John Rumm wrote:

Everyone seems to be misreading this... ;-)



Cross sectional view:

#C|
#C|
#C|
#C|
/====F
BB#C|
BB#C|
BB#/
BB#
#
#
#
K W O

B = boiler, F = boiler Flue, C = disused chimney, K = In kitchen,
W = Wall, O = Outside

There would be no joins - the chimney is only 12" thick and the flue
would go across it, not up it.

(this is only an academic discussion, since in reality a quick dog leg
in the kitchen will let the new flue miss the chimney and that ought to
cause less confusion - which is generally a good thing)


I cannot see *anything* logically wrong with that - especially as you
could clearly get an unjointed flue section right through the chimney so
no hidden joints.

The next logical option would be to bore a bigger hole right through
then line that with a big metal sleeve then pass the flue through,
sealing on the outside, bit like passing a gas pipe through a cavity wall.

Actually when you think about it, what's the difference between the
above and passing a flue through a cavity wall?

Well indeed - its already a dual skinned arrangement... its one of those
cases where it somehow feels not right, but I can't think why.

(although I suppose it would be harder to core drill and get both holes
in line)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article ,
John Rumm writes:
On 11/08/2014 12:46, Tim Watts wrote:
On 11/08/14 11:36, John Rumm wrote:

Everyone seems to be misreading this... ;-)



Cross sectional view:

#C|
#C|
#C|
#C|
/====F
BB#C|
BB#C|
BB#/
BB#
#
#
#
K W O

B = boiler, F = boiler Flue, C = disused chimney, K = In kitchen,
W = Wall, O = Outside

There would be no joins - the chimney is only 12" thick and the flue
would go across it, not up it.

(this is only an academic discussion, since in reality a quick dog leg
in the kitchen will let the new flue miss the chimney and that ought to
cause less confusion - which is generally a good thing)


I cannot see *anything* logically wrong with that - especially as you
could clearly get an unjointed flue section right through the chimney so
no hidden joints.

The next logical option would be to bore a bigger hole right through
then line that with a big metal sleeve then pass the flue through,
sealing on the outside, bit like passing a gas pipe through a cavity wall.

Actually when you think about it, what's the difference between the
above and passing a flue through a cavity wall?

Well indeed - its already a dual skinned arrangement... its one of those
cases where it somehow feels not right, but I can't think why.

(although I suppose it would be harder to core drill and get both holes
in line)

My biggest worry would be the structural integrity of the chimney
stack, particularly near the corbeling.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Mon, 11 Aug 2014 11:36:10 +0100, John Rumm wrote:

Everyone seems to be misreading this... ;-)

I didn't ... B-)
There would be no joins - the chimney is only 12" thick and the flue
would go across it, not up it.

Others have mentioned stones etc coming down the chimney, I'll add to
that a possibly corrosive atmosphere so a metal flue might not last
very well.

I'd go with the "gas pipe across wall cavity" liner approach. Totaly
isolated from the old chimney path for the new boilers flue and using
a decent bit of somthing for the liner physical protection as well.

--
Cheers
Dave.

On 11/08/2014 13:22, Andrew Gabriel wrote:
In article ,
John Rumm writes:
On 11/08/2014 12:46, Tim Watts wrote:
On 11/08/14 11:36, John Rumm wrote:

Everyone seems to be misreading this... ;-)



Cross sectional view:

#C|
#C|
#C|
#C|
/====F
BB#C|
BB#C|
BB#/
BB#
#
#
#
K W O

B = boiler, F = boiler Flue, C = disused chimney, K = In kitchen,
W = Wall, O = Outside

There would be no joins - the chimney is only 12" thick and the flue
would go across it, not up it.

(this is only an academic discussion, since in reality a quick dog leg
in the kitchen will let the new flue miss the chimney and that ought to
cause less confusion - which is generally a good thing)


I cannot see *anything* logically wrong with that - especially as you
could clearly get an unjointed flue section right through the chimney so
no hidden joints.

The next logical option would be to bore a bigger hole right through
then line that with a big metal sleeve then pass the flue through,
sealing on the outside, bit like passing a gas pipe through a cavity wall.

Actually when you think about it, what's the difference between the
above and passing a flue through a cavity wall?

Well indeed - its already a dual skinned arrangement... its one of those
cases where it somehow feels not right, but I can't think why.

(although I suppose it would be harder to core drill and get both holes
in line)

My biggest worry would be the structural integrity of the chimney
stack, particularly near the corbeling.

Yup I think that probably is the greatest unknown - the hole would
probably be above the corbelled section, but one does not know what is
sitting in the bottom of it. I think for the sake of a slight increase
in flue price its worth side stepping it with a short run to the side
and an elbow.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/