>I didn't think to estimate the heat-rise. I tried
>duplicating the failure by setting up a litle PIC
>circuit that just turns this thing on and off. I'm
>even discharging the cap via a relay to ensure it
>starts at zero. 2,500 cycles later it is still ticking.

However what temperature are you doing this at? It strikes me that the real
problem is not the resistor, but the capacitor. As someone else pointed out,
the USA gets real cold in January. What are the specs for the capacitor
at -10C? It sounds to me like it may be going low resistive (or possibly
even something else subsequent in the circuit changes characteristics) so
you are not actually seeing the inrush pulse you expect, but rather a
constant high current.

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