Process of electrical contact heating can be
described in spherical model of temperature
distribution in electrical contacts introducing by R.
Holm. In this research two phase spherical Stefan
problem is considered and solution represented in series
for integral error function and heat polynomials with
undetermined coefficients. All coefficients are founded.
Series convergence is proved by condition of constant
temperature on the free boundary.
Keywords : Stefan Problem, Heat Polynomials, Integral Error Function, Free Boundaries, Faa-Di Bruno.