Our existing back boiler has been removed from the living room
fireplace and replaced with a conventional boiler that lives elsewhere.

The flue liner that was attached to it has been left in place and is
hanging down into the fireplace recess. We know this needs to be
removed as it has reached it's end of life and can't be reused.

The house was built c1910 and I am making the assumption that the
brickwork will not be suitable to be left unlined. Looking in the loft
I can see cracks in the mortar that mean the chimney is unlikely to be
sound and suitable for use without any sort of liner.

From the fires manual it looks like the solution in this situation is
to install the fire inside a gas flue box which connects to a 125mm
flexible flue liner. The gas fire is rated at 3.5kw and the manual
states that a 125mm flue is suitable. No additional ventilation is
required in the room for this fire according to the size of the room.

I have found what looks like a suitable box at:

http://www.selkirk.co.uk/Systems/gas...s.htm#Recessed

This meets the dimensions required in the gas fire manual and would
need to be connected to a new flexible liner which terminates to a GC1
terminal.

My intention is to install the flue myself (this is covered by building
regulations which means I will need to notify building control.. and
pay?). I will also install the fire surround myself ready for CORGI man
to make the gas connection and drop the fire in place. I will also
carry out the relevant smoke tests myself beforehand to make sure the
flue draws correctly although I will be expecting CORGI man to do these
tests again.

Questions (Ed Sirett are you out there??):

1) My research has also found that in some instances you can install a
debris plate rather than a complete flue box? This would be easier and
cheaper as I have rebuilt the fire place opening to the exact size of
the gas fire. If I have to now install a flue box I am going to have to
make the opening slightly bigger which will be a real PITA. In what
circumstance is a debris plate acceptable rather than the complete flue
box ?

2) This is difficult to explain but here goes.. The fire place back
panel when fixed to the fire surround does not sit flush tightly
against the wall. Although the surround itself is tight to the wall the
back panel is slightly inset. Should this void be packed out with
fireproof board or similar ?

3) Should the flue box protrude from the builders opening so that it
sits against the back panel? This would solve q2.

Any further help with this is much appreciated. Should I face up and be
leaving this to the pro's ?

On Thu, 25 May 2006 14:25:06 -0700, andy.hide wrote:

Our existing back boiler has been removed from the living room
fireplace and replaced with a conventional boiler that lives elsewhere.

The flue liner that was attached to it has been left in place and is
hanging down into the fireplace recess. We know this needs to be
removed as it has reached it's end of life and can't be reused.

The house was built c1910 and I am making the assumption that the
brickwork will not be suitable to be left unlined. Looking in the loft
I can see cracks in the mortar that mean the chimney is unlikely to be
sound and suitable for use without any sort of liner.

From the fires manual it looks like the solution in this situation is
to install the fire inside a gas flue box which connects to a 125mm
flexible flue liner. The gas fire is rated at 3.5kw and the manual
states that a 125mm flue is suitable. No additional ventilation is
required in the room for this fire according to the size of the room.

I have found what looks like a suitable box at:

http://www.selkirk.co.uk/Systems/gas...s.htm#Recessed

This meets the dimensions required in the gas fire manual and would
need to be connected to a new flexible liner which terminates to a GC1
terminal.

My intention is to install the flue myself (this is covered by building
regulations which means I will need to notify building control.. and
pay?). I will also install the fire surround myself ready for CORGI man
to make the gas connection and drop the fire in place. I will also
carry out the relevant smoke tests myself beforehand to make sure the
flue draws correctly although I will be expecting CORGI man to do these
tests again.

Questions (Ed Sirett are you out there??):

1) My research has also found that in some instances you can install a
debris plate rather than a complete flue box? This would be easier and
cheaper as I have rebuilt the fire place opening to the exact size of
the gas fire. If I have to now install a flue box I am going to have to
make the opening slightly bigger which will be a real PITA. In what
circumstance is a debris plate acceptable rather than the complete flue
box ?

You may need to ask the manufacturers what is acceptable.
If they say that a back-box + flue liner + terminal is OK, that may be the
only way or it may be one way.


2) This is difficult to explain but here goes.. The fire place back
panel when fixed to the fire surround does not sit flush tightly
against the wall. Although the surround itself is tight to the wall the
back panel is slightly inset. Should this void be packed out with
fireproof board or similar ?

3) Should the flue box protrude from the builders opening so that it
sits against the back panel? This would solve q2.

Any further help with this is much appreciated. Should I face up and be
leaving this to the pro's ?

There is so much that can go wrong with a fire installation...
Every job seems to be different and each one seems to have particular
problems....

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards