Bare HydroHeater

HydroHeater without the insulation and cover.  This is the way to go if you already have a system that works most of the time and you just want a backup for those times it does freeze.  Maybe you keep your hose under your jacket, mabye you never forget to blow back, maybe you drink pure alchohol (not a good idea, doesn't work anyway).  Whatever the case, it's gonna freeze sometime.  This would be a great backup for those "oops" moments.