PURPOSE: To achieve the improvement of the efficiency of equipment, for making the heat accumulator small in size and energy-saving by an arrangement wherein the controlling circuit is so arranged that, in the climate under which heating is necessary, heat is accumulated during day time and an auxiliary operation is performed during night when necessary and, in the climate under which cooling is necessary, cold heat is accumulated during night and the auxiliary operation is performed during day time in a heat pump type air conditioner utilizing solar heat.

CONSTITUTION: Required time program, for example, at cooling operation, 19W7 o'clock is the time for cold heat accumulation and 7W19 o'clock is the time for auxiliary operation and, at heating operation, 19W7 o'clock is the time for auxiliary operation and 7W19 o'clock is the time for heat accumulation, is set in a programmed timer 12. According to the arrangement described above and to the set program in the programmed timer 12, contacts a and b of a cold water temperature controller 24 are changed-over during cooling and contacts c and d of a hot water temperature controller 25 are changed-over during heating in the positions as indicated with dotted lines and solid lines in order to perform auxiliary operation and cold heat accumulating operation or heat accumulating operation. As a result, the improvement of the efficiency of equipment, the making of the heat accumulator small and the energy-saving are contrived.