摘要:
A heat exchanger system, a fuel control system therefor and methods of making the same are provided, the fuel control system having an electrical circuit means that comprises an ignition trial portion, a flame sensing control portion and a timer portion that comprises a counter having a plurality of outputs and a timer that clocks the output of the counter on each discharge of the timer, the timer portion also comprising a capacitor, a trial time resistor and a wait time resistor that are selectively placed in series with the capacitor by the counter when clocked to certain outputs by the timer to determine an ignition trial time period and a wait time period.
摘要:
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.
摘要:
A fuel oil burner utilizing a hot surface ignition with an ignitor that is fully sintered and has essentially no porosity, a circuit for applying AC line voltage to the ignitor and to a blower motor, an AC-to-DC converter for providing twelve volts DC for operation of a control circuit that has a first time constant circuit for preheating the ignitor and maintaining the ignitor at an ignition temperature for a predetermined ignition trial period of time, a second time constant circuit for starting the blower motor and providing fuel to the combustion chamber for a predetermined time concurrent with the ignition trial period, and a third time constant circuit that either maintains the fan blower in its energized state if a flame of sufficient magnitude and frequency is detected and for de-energizing the blower motor if the flame is not detected in less than one second after the ignitor is de-energized. A lock-out circuit is provided such that if no flame is detected, the unit cannot be restarred without first removing power and then reapplying power to the unit.
摘要:
An anti-bounce system for control of critical loads is provided. A control system contains two subsystems. The first subsystem functions for normal control of the critical loads, but has a relatively long information processing time. This long time might prevent the system from controlling the loads in a safe manner. The system has a second subsystem that has a very rapid processing time. Both of the subsystems are connected to the load by coupling means to monitor as a feedback signal the exact state of the loads. The second subsystem overrides the first, and disconnects power whenever there has been an interruption of power for a short period of time.
摘要:
Burner control apparatus includes a control device for actuating an ignition control means, and a timing circuit for providing an ignition timing interval which extends beyond flame detection for a timed interval. The timing circuit is actuated in response to a request for burner operation and the control device is energized in response to the actuated timing circuit. The control device is maintained energized if a signal from the flame sensor is received before the end of the ignition timing interval, and the control device is deenergized and lockout circuitry is energized in the absence of a signal from the flame sensor. Main fuel supply is delayed for the timed interval to provide pilot flame stabilization.
摘要:
A heat exchanger system, a fuel control system therefor and methods of making the same are provided, the fuel control system having an electrical circuit means that comprises an ignition trial portion, a flame sensing control portion and a timer portion that comprises a counter having a plurality of outputs and a timer that clocks the output of the counter on each discharge of the timer, the timer portion also comprising a capacitor, a trial time resistor and a wait time resistor that are selectively placed in series with the capacitor by the counter when clocked to certain outputs by the timer to determine an ignition trial time period and a wait time period.
摘要:
A burner control apparatus for use with a furnace installation that has an operating control to produce a request for burner operation, a flame sensor to produce a signal when flame is present in the monitored combustion chamber, and one or more devices for control of ignition and/or fuel flow. The burner control apparatus comprises lockout apparatus for de-energizing the control apparatus, a control device for actuating the ignition and/or fuel control devices, and a timing circuit that provides four successive and partially overlapping timing intervals of precise relation, including a purge timing interval, a pilot ignition interval, and a main fuel ignition interval. The present invention further includes a burner control system which verifies the proper operation of certain sensors in a burner or furnace including particularly the air flow sensor. Additionally, the present system also prevents an attempt to ignite a burner if a condition is detected which indicates that the air flow sensor has been bypassed or wedged in the actuated position.
摘要:
When a call for heat is established, a flame relay is actuated for a predetermined time by means of a cycling timer. Upon this initial actuation, the flame relay inhibits a checking relay and initializes a trial-for-ignition (or simply "ignition") timer. After the cycling timer times out and the flame relay has been completely cycled, which established operativeness of the flame relay and flame sensing circuitry, the checking relay is enabled and actuated for the ignition period. The checking relay then actuates the pilot valve and a spark generator to start a pilot flame. If a flame is sensed, before the ignition timer times out, the flame relay actuates the main valve and establishes a holding current for the ignition timer so that the checking relay continues to be energized. If a flame is not sensed during the trial period, the ignition timer disables the checking relay, thereby de-energizing the pilot valve before the main valve is opened. If there is a fault in the flame relay or flame sensing circuitry, the checking relay is inhibited from operating. Both timers are preferably electronic timing circuits using capacitors in such a manner that circuit faults do not cause system malfunction. In an alternative embodiment, separate flame sensing circuits control the operation of the flame relay and the ignition timer.
摘要:
An electronic programme timer means of solid state construction, for a fuel burner, said programme timer means comprising a control switch for initiating operation, a plurality of sequencing relays, flame sensing means connected to voltage comparators, voltage ramp generator, voltage follower and level detectors with output connected to said comparators for controlling said sequencing relays, feedback means to said comparators to ensure correct switching, temperature sensing means for switching said timer means and pressure sensing means for checking operation of blower purging means.