An apparatus, cooking appliance and method functionally verify a gas burner that is controlled by two or more electronically-controlled gas valves coupled in series with one another. Functional verification is performed during ignition and/or shut off of the gas burner at least in part by sequencing the activation and/or deactivation of the gas valves and testing the ignition state of the gas burner while one of the valves is activated and the other is deactivated.

A method for evaluating a quasi-stationary pressure difference detectable by a sensor at a gas boiler. The gas boiler has a mixing device (4), a fan (5), a main flow regulator (3), .a control valve (2) and a safety valve (1). The sensor detects a differential pressure between a pressure (p2) at a measuring point upstream of the main flow regulator (3) and downstream of the control valve (2) and a reference pressure (p0, p1) at a reference measuring point. The sensor transmits a signal to an electronic evaluation system. The electronic evaluation system compares the differential pressure during a pre-purge phase, wherein the safety valve (1) is closed, with the differential pressure after the pre-purge phase and detects an error by the comparison.

A method of monitoring a flame rod of a furnace including: detecting an average current of the flame rod during a burn cycle of the furnace; determining a burn time of the burn cycle of the furnace; and determining a remaining life of the flame rod based on at least the average current and the burn time.

A first reset switch is attached to a combustion controlling device. A second reset switch is installed at a remote place distant from the combustion controlling device. A first reset input from the first reset switch is received without any restriction to release the lockout. A reset input from the second reset switch is received with any restriction to release the lockout. Specifically, when the lockout releases are performed for a predetermined number of times or more upon receiving the reset input before a predetermined time elapses after the lockout has been released upon receiving the initial reset input, the release of the lockout upon receiving the reset input is prohibited until the predetermined time elapses.

Various embodiments include a control system comprising: an ionization electrode; a flame sensor; a first signal conditioning circuit for the ionization electrode; a second signal conditioning circuit for the flame sensor; an output unit; and a processor. The processor: receives a first and a second ionization signal indicative of ionization currents from the first signal conditioning circuit; receives a first and a second flame signal indicative of radiations originating from a flame via the second signal conditioning circuit; produces a derived ionization signal as a function of the first and the second ionization signals; produces a derived flame signal as a function of the first and the second flame signals; determines if a flame lift-off condition exists based on the derived ionization signal and the derived flame signal; and if a flame lift-off condition exists, produces a safety signal and transmits the safety signal to the output unit.

Various embodiments include a control system comprising: an ionization electrode; a flame sensor; a first signal conditioning circuit for the ionization electrode; a second signal conditioning circuit for the flame sensor; an output unit; and a processor. The processor: receives a first and a second ionization signal indicative of ionization currents from the first signal conditioning circuit; receives a first and a second flame signal indicative of radiations originating from a flame via the second signal conditioning circuit; produces a derived ionization signal as a function of the first and the second ionization signals; produces a derived flame signal as a function of the first and the second flame signals; determines if a flame lift-off condition exists based on the derived ionization signal and the derived flame signal; and if a flame lift-off condition exists, produces a safety signal and transmits the safety signal to the output unit.

A safety auditor is designed to perform opening and closing of every safety switch that is used in an industrial bakery oven. Every pressure sensor can be tested for on and off states. The low gas pressure switch can be vented and the high gas pressure switch pressurized. All thermocouples associated with the high temperature circuits are tripped. Fans are started and stopped over a communications signal or via the hard-wired interface as required to generate the safety testing. Once the safety testing is complete, the results along with time, date, name of tester, pass or fail will be printed out via a small kiosk printer. This ticket can then be filed in an office. As the operation is easy to do and requires little effort, it is much more likely to be performed and therefore safer for the host bakery.

A safety auditor is designed to perform opening and closing of every safety switch that is used in an industrial bakery oven. Every pressure sensor can be tested for on and off states. The low gas pressure switch can be vented and the high gas pressure switch pressurized. All thermocouples associated with the high temperature circuits are tripped. Fans are started and stopped over a communications signal or via the hard-wired interface as required to generate the safety testing. Once the safety testing is complete, the results along with time, date, name of tester, pass or fail will be printed out via a small kiosk printer. This ticket can then be filed in an office. As the operation is easy to do and requires little effort, it is much more likely to be performed and therefore safer for the host bakery.

Disclosed are systems and methods for automated furnace inducer sensor output verification. A furnace may include a sensor, such as a transducer, that may be used to measure pressure within the furnace (for example, pressure resulting from the operation of a draft inducer blower and/or any other component of the furnace). It is possible that the data produced by the sensor may remain relatively fixed for a given period of time. However, this makes it difficult to determine if the data is valid or if the sensor is malfunctioning. Given this, an algorithm is used to change a motor speed of the inducer blower. The subsequent data that is produced by the sensor is then monitored to determine if an expected change in the data occurs. If the change does not occur, then it may be determined that the sensor is malfunctioning.

A system for checking high fluid pressure and low fluid pressure limit switches for valves and fluid supply to a fluid consumption appliance. The system may incorporate one or more pressure sensors at a fluid valve to detect an amount of fluid pressure. The one or more pressure sensors may be connected to a processor. The high fluid pressure and low fluid pressure sensor limit switches may also be connector to the processor. A display and user control may be connected to the processor.