Anybody know of a product I could insulate my chimney with?
I bought the stove used and have used it this way for the last 10+ years but feel
Insulating it would help with the efficiency of the stove.

Why do you guys think?

You can buy chimneys with the insulation included, it is up to you how you want to go about it.

Rock wool insulation

I have an outdoor boiler also and I have never seen an insulated chimney on one. Just wondering if there is a reason for it.

I see no need for it.... In fact, that the first time I've ever see a chimney on a boiler more than about a foot tall. I don't see how insulating that will make it more efficient.

An insulated stove pipe would reduce creosote but I'm not sure how much it would improve efficiency

Money would be better spent on insulating the water lines better.

That one definitely need replacing, before it falls over.

The insurance up here makes you put the burners at least 50 feet from any building and pipes replaced every 3 years. and a metal 8 foot guard in the pipes to stop fire burn in the water pipes.

Don't go with a insulated one too much of a chance of cracking and cresol building up in the wool and it becoming a blow torch when it goes.

People I know have an old school bus they take the seats out, load it up and park it 10 feet from the stove, so come fall there is 1600 cu feet od dry wood to burn. And no snow drift to fight.
The windows are great driers and it is turned about July for the other side to get a shot.

I don’t see that happening, it’s around 1/4” thick steel.
I think I‘ll leave good enough alone.

Push a screw driver into those red areas, the acids have leach right through the metal.

I shouldn't even comment. But, why would you think insulating the chimney on an outdoor boiler might make any difference in the boiler's efficiency???

If you've been running a used furnace for a decade; you'd be better off checking the PH level of boiler water to insure corrosion has not affected the water jacket!!

Every 3 % you drop the wood moisture by , you increase the BTU's by 10 %
Basically you don't have to boil the moisture out of the wood.

Looks like you clean out the drop zone regularly.
I did a study for Forestry Canada on firewood and the drying effects and the BTU's, that's what Y2K got all of us thinking.
40,000 data point was not as easy to calibrate back in DOS period days

Stainless pipe should be insulated already.