Can I wrap my Oil fired Boiler with Rockwool to slow down the heat loss

[stejus]

Since installing a wood stove, I only use the Boiler to heat water with an internal tankless heater. I am trying to add insulation around the entire boiler to slow down the heat loss due to colder basement temps in the winter. It can get down to low 40's in the dead of winter.

I was thinking ROXUL Rookwool. This stuff is firm and can be cut to shape. Am I wasting my time? My goal is to reduce the number of times the boiler kicks in to heat the water.

 

[webbie]

I would say yes...in general.
If you feel a lot of warmth on the outside of your boiler jacket, it might indicate excess heat loss.

Given that your basement is colder than most, I would guess it might be worth your while. Note that many grades of fiberglass can handle boiler temps, so if it is much cheaper you can consider rigid panels of some sort. If the entire unit is water jacketed, then the highest temps you are likely to see are about 300 F.

 

[stejus]

Half the basement is above grade with a few windows and doors (walk out basement). I didn't realise I could use fiberglass rigid panels. I know the flue temp is 500 something degrees so I can't imagine the top surface any hotter than that. The boiler does has fiberglass insulation inside the boiler jacket, so I guess it's safe to use on the outside. Yes, cheaper with the same R value and available to purchase at many retail outlets. Thanks for confirming.

 

[webbie]

A slightly higher temp fiberglass may be available in places like Drywall supply houses, etc. - they also have mineral fiber and rock wall batts and panels. Make sure you don't use any with combustible facing.