Floor standing boiler

[Tim Lamb]

I am contemplating a major refurb/extension of a timber frame dwelling. Current heating, micro bore fed, wall hung radiators and relatively recent wall mounted gas fired system boiler.

There is also a central brick/lined flue and a gas fired Rayburn cooker.

I would like to fit wet underfloor heating throughout and use pressurised DHW.

Does anyone have views/experience of centrally located, floor standing gas boilers? Efficiency, noise level, cost, etc.

Rayburn combustion air is via air brick so draughty! Could be ducted through new ceiling void.

[spuorgelgoog]

Is the existing boiler unsuitable for the new heating load?

Running flues through ducts can be expensive and there are access requirements for inspection. A straightforward through-the-wall flue is usually a lot simpler and cheaper.

Owain

[Tim Lamb]

It is in the way of a proposed 40% extension. I guess it would stretch with the relaxed requirement of underfloor heating. DHW and airing cupboard could best go next to the central flue. Bathrooms, kitchen are scattered around the outside walls so central is as good as anywhere. Up one end on an outside wall would lead to some long pipe runs.

Flue would be existing lined chimney already accepted for gas fired cooker. Just thinking of ducting the air supply.

[Roger Mills]

And don't forget the condensate drain. This is usually easier if the boiler is on an outside wall.

[Tim Lamb]

Ah! Good point. I could probably gravity run it to a rainwater soak gulley.

[GB]

My experience is that GasSafe engineers tend to hate vertical flue boilers and will look for an excuse to fail them.