Obviously a lot of taleneted engineering types on here. So, must be thread for engineering advice. I'll start. Got an old (20 years) oil fired central heating boiler that sits in an alcove in the house with the the flue going through the roof)and it's a bit fecked. Got someone in to look at getting a new one, tells me what I need is is an external boiler, run pipes under the floor yadaya. My old boiler is not a condensing boiler if you fit a new one it's legally required to be a condensing boiler. There was me thinking pull out the old one fire in a new one job done. Thoughts?