A spacecraft equipment panel (20) including heat pipes (HP1, HP2, HP3) operable in a zero-gravity environment for cooling the equipment (E1, E2, E3) mounted to the panel is not operable in an Earth-gravity environment because the two-phase working fluid in the heat pipes (HP1, HP2, HP3) tends to pool at the bottom of the heat pipe when the heat pipe is vertical. An apparatus and method for overcoming this condition employs infrared lamps (IR1, IR2, IR3) positioned on a mounting frame (120) to heat the bottoms of the heat pipes (HP1, HP2, HP3) to vaporize the working fluid therein, whereby the heat pipes (HP1, HP2, HP3) become operable for transporting heat while in a vertical orientation and under the influence of gravity.