OWB urethane foam caught fire - burned

[Bob.blustar]

I bought an used older outdoor wood boiler. During the set up, I took off some of the external sheet metal to replace the water temperature gauge. Then I was able to see that 60% of the yellow polyurethane foam insulation and charcoaled, burnt to a crisp. And the stuff that was burned thru was black where it touched the steel water jacket.
I haven't contacted the manufacturer yet about this so I'm not naming them publicly. But I have a feeling they won't do anything because it was bought 3rd hand. And they are a small time manufacturer.
I also think that maybe it was fired without any water in it or it all leaked out of the pipes or pump connection. That's the only way I can think that it got hot enough to burn the polyurethane foam.
What should I replace it with? Rockwool?
Thoughts anyone?
Thanks

 

[Bob.blustar]

Corrections: was charcoaled, burnt to a crisp.
And the stuff that wasn't burnt thru was black where it touched the steel water jacket.

 

[olyman]

don't be near,,any urethane burning...emits phosgene gas,,kills near instant...

 

[Sandhill Crane]

any urethane burning...emits phosgene gas,,kills near instant...

Good to know!

 

[Marley5]

I totally agree with you......was fired without water/lost water.

Rockwool would be a solid choice.

 

[NSMaple1]

I dont think I would risk buying an older used OWB period, let alone one that has been through that. It could have leaks that caused that to happen for all we know. I would seriously consider cutting losses now.

 

[Mustang71]

don't be near,,any urethane burning...emits phosgene gas,,kills near instant...

That's the good stuff. I get that every now and again when I'm brazing up an old r22 system it takes your breath away instantly.