PURPOSE: To enable a presence of a person to be confirmed and to enable an operation of a heater to be controlled by a method wherein a collector type infra-red ray sensor is fixed to the heater.
CONSTITUTION: A heater 2 and a collector type infra-red ray sensor 3 are fixed to a frame of a heater. There are provided a,counting circuit 6 for counting an output of the infrared ray sensor 3; a count timer 7 for setting a count time; a discriminating circuit 8 operated when the count timer 7 times up; and a timer circuit 4 for resetting in response to an output signal of the discriminating circuit 8. Then, the discriminating circuit 8 performs a resetting of the timer circuit 4 when the number of outputs of the collector type infrared ray sensor 3 during the setting time of the count timer 7 exceeds a predetermined set number and an operation of the heater 2 is instructed only for a period of timer setting time.