Flue Alterations

[Rich Harris]

Hi all.

I am currently trying to make my fireplace opening suitable for a Valor Anthem DFE gas fire bought from B&Q.

The exisiting fireplace was to small in every dimension to accommodate the new fire. It is a precast single block Class 2 flue design, installed in 1986.

I have removed the one piece starter block at the base, thinking it would be a relatively straightforward matter of purchasing a new, wider one, but it now appears that this is much more problematic than envisaged.

Ideally I'd like to fit some new starter blocks and make good the joint to the gatherer block at the top.

Any advice, warnings tips gratefully received!

Rich.

[Andrew]

In article , Rich Harris writes

Sorry, DFE fires need a class 1 flue. Take it back and ask for a refund and look for a balanced flue fire from Kinder or Gazco instead. Ed will be along shortly hopefully to backup what I am saying.

[Rich Harris]

Andrew,

Thanks for the reply. I might have confused things by saying it was a DFE fire, as I understood it to be a generic description of the type. The instructions say the fire *is* suitable for a class 2 flue.

Rich.

[Andrew]

In article , Rich Harris writes

There may still be problems. Class 2 can refer to pre-cast and pre- fabricated flues. If your house was built in 1986 then it is possible that it has pre-cast flue blocks with a cross section of 12,000 mm2, which is not acceptable by modern standards. I am pretty sure that the 'class 2' that your fire refers to is the modern 'twinwall' 5 inch diameter flue. Does your house have flat walls in the room above the fire ?, or a chimney breast. If flat then it would seem to have pre-cast flue blocks that are part of the inner wall leaf. This (AFIK) is not suitable for a DFE fire.

As I say, Ed the resident registered gas installer will have more to say, or failing that you should take advice from any corgi registered installer or your local BCO.

Remember that DFE fires are designed to give a realistic fire effect which means lots of carbon monoxide (AFAIK), and anyway are horridly inefficient - typically 10Kw gas burnt and only 1 to 2 kW of heat.

If you put this in yourself (using the wrong type of flue) then sell the house it's your neck on the legal chopping block.

[Rich Harris]

Andrew,

Thanks again for your comments; mine inline.

The booklet for the fire says it is suitable for flues with a CSA of

12,000mm2. My house DOES have flat walls above and no chimney breast, and I agree with your assessment that it's pre-cast blocks within the inner wall leaf.

I also should have said at the outset that I had the original fire taken off by a CORGI guy, and he advised me that the opening was suitable for the fire I had bought.

Yeah, know about the inefficiency :-) !! It's only really going to be there to look nice, rather than be the primary heat source for the room. Not sure about the CO though - my understanding is that it's partial combustion that produces the stuff; if the fire is set up correctly it's mostly CO2 and water (although I appreciate that bad flueing could lead to impartial combustion etc...).

Definitely WON'T be fitting the fire myself!!! I am only doing the building work, and have agreed with the CORGI man a revisit for him to fit fire and gas piping.

Never mind my head on the block, there's no way I'm gonna poising my family for £100 quid's worth of gas work.

Rich.