Fbh questions

Only got it working this month get some noise from it when Engine switch off I no this is normal.
But no seen smoke from it yet. And how many miles should I run car before car temperature climes. At the moment I do about 1.5 miles before guage starts to clime and I get heat is that about right

There is a temp sensor behind the front grille which should activate the FBH at 5deg C or less. 1.5 miles seems about right for coolant temp rise compared to our TD4s.