  The dependence of the thermal pressure of hot galactic halos on a model
parameter describing the frequency of major reheating episodes during galactic
history is investigated. Pressure on the interface between interstellar medium
and the halo gas is especially interesting, since empirical evidence here
offers one of the simplest constraints on halo models. It is shown that
two-phase model of Mo & Miralda-Escud\'e is sufficiently robust with respect to
uncertainties in the average interval between reheating.

Astrophysics