I have an oil fueled boiler in a lower level with a 30' run of an 8" exhaust through a crawl space to the chimney. The temperature of the exhaust near the boiler is 700F and it drops to 250F near the chimney. I would like to insulate it with something to reduce the temperature drop so that the temperature is higher at the chimney. Any suggestions of insulation that could/should be used to wrap this exhaust?

Sounds like you are sending more heat outside than inside, just don`t sound right to me,, 700 degree exhaust,, even the 250f sounds outragious for exhaust,, you need someone to look your system over,, you are paying your money out to heat the world outside

You will also need a 1/4 inch per foot for minimum pipe rise. I would install a type L vent chimny or Metalbestos pre fab unit before I would run 30 feet. Adjusting that burner could be a problem with that long a run.

At last, the source of global warming revealed...

At last, the source of global warming revealed...


Here is the helper.

Child stars... where are they now? Unbelievable how far R2D2 has sunk...