Abstract: A solar heating panel includes a unitary rectangular shell having a low thermal conductivity urethane foam liner sandwiched between inner and outer fiberglass boxes. The inner box is impregnated with a dark coloring and has spaced raised support and expansion ridges extending traversely across its bottom. An integral lip located at the top of the shell stiffens its sidewalls and mounts a thermally insulated window comprised of paired sheets of glass separated by a sealed space. A thermal collector assembly adapted for placement within the shell on the support and expansion ridges is comprised of a serpentine heat transfer coil and an adjacent planar collector sheet which are integrally formed by joinder of a plurality of stamped unitary modular units dimensioned to be received within the collector shell. An inlet and an outlet pass from opposite ends of the heat transfer coil out of the shell through openings in its sidewalls.