Abstract: A control apparatus for repetitively verifying the integrity of a main fuel valve control circuit in a standing pilot burner system includes a probe circuit adapted to receive an electrical signal representative of the presence of a standing pilot flame and a first circuit which coacts with the probe circuit for energizing a first relay in response to the electrical signal. A second circuit is adapted to receive a heat demand signal and coacts with the first circuit for sequentially disabling the probe circuit, de-energizing the first relay, energizing a second relay, re-enabling the probe circuit and re-energizing the first relay to actuate a main fuel valve.