DIY: A/C Insulation

[CTScott]

Originally Posted by auxmike

Is this a safe practice?
If so, why did'nt Toyota do it in the first place?
Wonder if that foam could MELT with the heat under that hood.....

I was thinking the same thing. There are high temp and ultra high temp pipe insulations, but they are pricey.

Polyethylene pipe insulation (which is the kind you get at home improvement centers) is only rated to 180F or 200F.

Silicone pipe insulation is rated for 500F, mineral wool can handle 800F, Flexible ceramic at 1500F, etc. McMaster-Carr has a wide selection of industrial pipe insulation.

The other issue besides temp rating is fire rating (ASTM E84 rating). We ran into an issue UL testing a battery pack because of insufficient rating on the closed cell foam we were using the keep the batteries from banging around.