I have an 25yr old boiler and will upgrade to a new one before I have to get a condensing variety. I understand that modern boilers have much lower flue gas temperatures, and the current flue is 4inch cast iron up to a soot door (which is about 8ft above the boiler room floor) in a brick chimney which is lined with glazed pipe. There is no chimney terminal.
The question is: Do I need a stainless liner and flue terminal? Does the liner have to be straight through to the boiler or do you still have the soot door etc.?
I will get an OFTEC chap to Part L the installation at the end
Thanks
Ian H, Cambridge