New Boiler + Radiators

That may not follow. Combis often have higher gas flow requirements and the existing piping for an old conventional boiler might not be sufficient.

Also, if you replace a conventional boiler with a combi, you'll need a feed to the hot taps from the boiler position rather than from the hot cylinder - and you'll presumably want to have the cylinder and header tanks etc. - plus surplus pipework - removed.

Bearing in mind the scrap value of copper nowadays .

ballpark 2 grand

about £700

do they really need replacing?

If you DIY - yes. But if you have to pay someone to do it, the labour cost will outweigh what you get for the scrap copper. I got just over £30 for my old cylinder[1] and a few bits of copper pipe and brass fittings. You can't buy much labour for that!

I was thinking that - but if you use a condensing boiler having oversized radiators is an advantage. If they were fitted before cavity wall insulation or were oversized in the first place I would leave well alone. Or just replace the unsightly ones or ones in a cold room.

I'd also be tempted to hang onto the hot water cylinder if the rest of the hot water system is working OK. It's no different to some of the current heat store systems but with a remote tank!

Not that much of an advantage that replacing sericeable ones would make economic or ecological sense, methinks.

Thanks for the replies, everyone. I think I'm just looking for the most economical way of doing this. I'm not fussed about having something with bells and whistles, as the house stays reasonably warm most of the year.

I only mentioned having the radiators replaced as the guy in B&Q, who was a ex-boiler fitter suggested changing the radiators as well. In fact he said if I didn't it'd be kind of cheapskate.