Flue lengths available on oil boiler

[Terrywookfit]

Check with Grant tech,but it is my understanding that both sizes of flue are suitable up to 12m.

Look at "White system vertical balanced flues".

It is the twin wall liners that are only suitable up to 26kw.

The flexible WB ones are meant for lining an existing chimney.

 

[Saltire]

check out the Grant and Worcester web sites, failing that nip into your local plumbers merchant, they should have flueing guides etc...

As to the best oil, i sell both in almost equal numbers, the feedback i get would suggest Grant are slightly ahead on reliability and Efficiency...