Boy, I'd love to hear their explanation for why auto antifreeze is no
good but ethylene glycol is ok. The antifreeze has a lubricant for the
water pump and an anticorrosion package but all that together is less
than 1%, it's all compatible with copper tubing, steel, and cast iron,
and the electrical conductivity is pretty low to avoid problems with
dis-similar metals in the engine and radiator. I just thought the
propylene glycol based antifreeze would be better here since it's
nontoxic. I'm too lazy to look up the flash point but I don't think the
glycols burn much unless there's another source of fuel to keep them
going; even water hitting molten steel is going to be violent enough
that I personally don't think the glycol would be worse, but I've never
done the test ... :-).

--
Regards,
Carl Ijames carl.ijames at verizon.net

"Alan Black" wrote in message
m...
I asked the Inductotherm people about that, they say don't use
automotive
type antifreeze, but you can add ethylene glycol to the water in very
cold
areas.
Alan Black

"Carl Ijames" wrote in message
...
How about circulating propylene glycol instead of water, inside a
copper
tubing load coil? Nontoxic, basically nonconducting in case of a
leak,
and pretty cheap (Sierra antifreeze is about $7/gallon here in the
US).
It's a little viscous until it warms up, and doesn't have the heat
capacity of water, but should be safer for you.

--
Regards,
Carl Ijames carl.ijames at verizon.net