Abstract: An oil burner control system is disclosed in which recycling between a loss of combustion to re-establishment of combustion is limited by counting the number of times recycling occurs and causing a the system to stop recycling and go to lockout after the count reaches a predetermined value.

Abstract: An oil burner control system is disclosed in which an extended time may be temporarily selected, in situations such as initial set up or periodic maintenance, for priming the pipes, filters and pumps, before a safety lockout of system operation occurs, while otherwise leaving the normal safety lockout functions intact. An igniter in the system operates in an “intermittent” mode during the temporarily selected extended time, and otherwise operates in an “interrupted” mode.

Abstract: Improved lockout control in oil primary controllers for oil heating systems which allows a reasonable number of user resets and ignition retries in the event of lockout, while minimizing the unwanted accumulation of oil in the combustion chamber of the heating system. When the oil primary goes into lockout mode due to failure of combustion to take place, the oil primary is placed in a restricted mode of operation in which a limited number of reset activations and combustion retries may be attempted. If they are unsuccessful, a waiting time interval is then imposed between further successive attempts. The lockout or trial for ignition time may also be reduced for subsequent attempts, to minimize flooding. Normal operation is returned once a successful combustion cycle has been achieved.

Abstract: A controller for a system has two or more operating modes. The controller operates according to a different control algorithm in each operating mode. A manually operable switch typically used for sending a reset signal to the controller, may also be used to change operating modes. The controller changes operating mode when it detects that the switch is manually operated during a preselected phase of controller operation, typically when power is first applied. The disclosed embodiment allows up to four different operating modes to be selected. A first selection of operating modes can occurs if the switch is held closed during startup and then immediately released. A second selection of operating mode occurs if the switch is pressed within a preselected time interval after power is first applied to the controller. Both selections can be made during a single start-up event.

Abstract: A sensor provides a status signal indicating a condition of an operating system to the operating system's control system. The sensor has an inherent variable quantity such as resistance whose magnitude indicates the operating system status. The control system includes a user-operable switch which when actuated signals the microprocessor to determine the approximate value of the sensor's variable quantity. The magnitude of the variable quantity is then indicated by a signal comprising one or more beeps of sound or flashes of light. The number of beeps or flashes indicates the approximate present magnitude of the sensor's variable quantity. In a preferred embodiment, the control system comprises a microprocessor programmed to control the operating system and to perform most of the functions of the invention.

Abstract: A flame rectification type flame sensor circuit and method in which a generator injects periodic pulses of alternating voltage into a flame region, the voltage across the flame region being processed by a filter/amplifier which, in proper operation, produces a non-zero output signal only during the time a flame is present and a pulse of alternating voltage is being supplied by the generator. Final indication of a flame is produced only if a non-zero output signal occurs during the time a pulse of alternating voltage is being supplied, and not during the time between successive pulses of alternating voltage. Failure of an electrical component in the filter/amplifier is indicated if a non-zero output signal occurs during the time between successive pulses of alternating voltage.

Abstract: A novel aqueous flowable concentrate of the herbicide 2-(.alpha.-naphthoxy)-N,N-diethyl propionamide is disclosed, displaying superior storage stability and dispersion and handling characteristics. The concentrate consists essentially of, by weight of the total concentrate:(a) from 10 to 60% of 2-(.alpha.-naphthoxy)-N,N-diethyl propionamide;(b) from 0.1 to 2.0% of a smectite clay;(c) from 1.0 to 10.0% of a water-soluble nonionic surfactant;(d) from 0.5 to 5.0% of a water-soluble dispersant; and(e) from 1.0 to 20.0% of a water-soluble freezing point depressant;the balance being water; the solid components have an average particle size of from about 5 to about 15 microns.