Abstract: A control system for regulating a flow rate of a heat transfer fluid in a heat transfer system, the heat transfer system having a heat transfer fluid flow path, flow control device for creating flow along the path, a fuel source for providing a combustible fuel to the path, an air source for providing combustion air to the path, and an assembly for combusting the fuel and air, the control system comprising a sensor for sensing a measured flow value at the air source, a controller for storing an optimum flow value at the air source and for storing a range of operating control values for the flow control device, the operating control values corresponding to the optimum flow value, a system for calculating a deviation between the measured flow value and the optimum flow value, and a system for varying the operation of the flow control means in accordance with deviation.

Abstract: An electronic control for a heating apparatus and specifically a deep fat fryer is provided. The electronic control includes a temperature sensor for sensing the temperature of a cooking medium during a cooking cycle. Cooking medium temperature sensed during the cooking cycle is utilized as a pointer to one of a plurality of time compensation values for corresponding temperatures stored in a memory. The time compensation corresponding to the sensed cooking medium temperature is retrieved from the memory and adjusted by an offset value determined in accordance with the setpoint temperature to obtain an adjusted time compensation value. The adjusted time compensation value is utilized in the adjustment of the cooking time.

Abstract: A deep fat fryer includes a controller operatively connected to a heating element for controlling the operation thereof to apply heat to a cooking chamber. A temperature sensor is disposed in the cooking chamber for measuring the temperature in the cooking chamber and communicating the same to the controller. The controller selectively operates the heating means to apply heat to the cooking chamber. Utilizing the output of the temperature sensor, the controller automatically determines whether the medium contained in the cooking chamber is water, liquid shortening or solid shortening or whether the cooking chamber is empty.

Abstract: An electronic control system for controlling a heating apparatus. The control system accurately controls the temperature of a medium, while minimizing the wear of heating element components.

Abstract: A diaphragm assembly for movement in response to a pressure increase exerted thereon comprised of a resilient flexible diaphragm having a first surface with a predetermined profile when said diaphragm is in a neutral, unflexed condition, the diaphragm having an opening formed therethrough.A rigid pressure plate is adapted to be positioned against the diaphragm. The plate has a contoured surface for mating engagement with the first surface of the diaphragm. The contoured surface has a recessed sealing surface dimensioned to form an open space between the plate and the diaphragm when the diaphragm is in the neutral, unflexed condition, and to enable the diaphragm to flex into sealing engagement therewith when sufficient pressure is exerted on said diaphragm. A first vent passage communicates the opening in diaphragm with the open space, and a second vent passage communicates the open space with the edge of the pressure plate.

Abstract: A device for monitoring the level of salt in a brine tank. The device includes a housing and a circuit within the housing connectable to an electric power source. An indicator is connectable to the circuit for indicating the existence of a first electrical state and a second electrical state. An actuator member is provided having a first position wherein the indicator member indicates the first electrical state and a second position wherein the indicator member indicates the second electrical condition. A biasing member having a predetermined force biases the actuator member towards the first position. A surface member is provided for resting on the upper surface of the material in the tank, the surface member having a weight greater than the predetermined force of the biasing member and a density greater than water.

Abstract: A control unit for a spa or hot tub system is disclosed. The control unit is safe and protects the user from electric shock when operating the various spa equipment. Also, the unit allows the control and operation of all the spa equipment from a single location. In one embodiment of the invention, a specific air pressure transmitter has been designed to actuate remote air switches of different spa or hot tub equipment.