"velovelo13" wrote in message
om...
I think I typed R299 instead of R290. R290 is propane.

That makes more sense. Errr, no on second thought it doesn't. Are you
aware that propane is flammable and under pressure is rather dangerous?

All kidding aside, the hydrocarbon refrigerant schemes are more than I care
to investigate let alone risk my neck for.

- Robert