[TR] Fuel percolation

[Randall]

> Not sure I follow you here, which liquid? 
> The Dust Off is a gas, it sprays out, with or without a little tube, 

Dust-Off is actually 1,1 difluoroethane, also known as R-152a (a
refrigerant).  Inside the can it is (mostly) a liquid under pressure.  When
you pull the trigger, normally you get vaporized R-152a out of the nozzle,
and the liquid inside the can literally boils to supply more vapor.  It's
mostly the boiling refrigerant that gets cold (this is the exact same
process using in your air conditioner).

It's an old electronics troubleshooting trick to invert the can, so liquid
comes out the nozzle.  Whatever you spray the liquid on will get very cold,
very quick, as the liquid boils away (at atmospheric pressure, it boils at
something like -25C).  The thermal shock will frequently make a marginal
component reveal itself (although it can sometimes damage components that
were fine before the treatment).

So that is the liquid I was talking about.

-- Randall