Circulating heat from wood burner...

The principles ok but not actually making it part of chimney, as you say it would seriously affect the performance of fire itself apart from the added danger of hot pipes around.

Ideally you need to fit a heat exchanger onto the existing flue or into chimney void that generally takes air from an outside source passes through the heat exchanger and then ducts the warmed air to where you want it.
How efficient will depend on heat available, length of pipe runs and whether you can insulate those pipes/ducts between heat exchanger and outlet.
Is it feasible yes, depends on your house layout, ideally a loft where heat exchange unit can go and ducts run, exchanger itself can be pricey but ductwork, insulation, vents reasonable as you can substitute for locally sourced product.

Or another option would be replacing salamander with a wood pellet fire that can heat & do C/H & H/W in this localised area, quite possibly a better long term solution and no logs

Thanks for the reply.

Doing something in the loft is not really an option as that is sealed and insulated with an airspace above the false ceiling.

There's a length of flue above the salamandra where a heat exchanger could go, but then the flue disappears into the wall, but as you say, you need air from somewhere to make that work.

Before I go down the route of pellet boiler/water/radiators etc, which could actually go somewhere else and heat that whole side of the house, but is expensive, would replacing the salamandra with a recuperador work? I find it hard to find information in English as to how these work exactly.

Thanks! Nick

Hi Nick

The link below is to how to use the heat wasted from the flue. It seems very interesting and worth a look maybe of help to you.

Peter " Dreams can come true "

http://heat-booster.com/page7/index.html

Basically a fire box with a larger box around it on 3 sides with one or more outlets to duct air to other rooms, generally fan driven draw air in from front of fire then around fire box out through ducts, basic heat exchanger, but same issues apply you need to get ducts to other rooms, longer the ducts the less efficient, I have 1 for sale with Inox surround only in 1 season we then replaced with a back boiler
http://www.solzaima.pt/catalogos/Brochu ... N%2010.pdf
the 2 squares on top of fire are where the square to round converters fit to duct air

I mentioned pellet stove if you keep size down then cost is also less so might be suitable as a local circuit system, as you scale up your looking at boiler size units that are dearer but also suited to garage other areas to install, not something you'd want in a living area in last post about heat recover if you remember we discussed something along Peter's link but there seemed to be issues on pressure & safety if I recall