Abstract: A method of controlling an expansion valve including the steps of: measuring a primary system condition; determining an error in the primary system condition; measuring a secondary system condition; determining an error in the secondary system condition; and modulating the expansion valve based upon the larger of the first or second error.
Abstract: A method of measurement. The method comprises the steps of (a) measuring a value, (b) forwarding the measured value as an analog signal, (c) dithering the analog signal to improve resolution and (d) converting the analog signal to a digital signal.
Abstract: A control valve assembly for flushing a sanitary fixture includes a burst valve for supplying flush water flow at the beginning of a flush cycle and an independently controlled bypass valve for providing trap reseal flow after the burst valve closes. The burst valve includes a timing sleeve cooperating with a lifting piston to define a timing chamber communicating with inlet pressure through an orifice. A piston collar cooperates with the lifting piston to define the bypass valve. A lifting chamber defined between the body and the lifting piston communicates with the outlet through a metering valve assembly. Actuation of the metering valve assembly empties the lifting chamber and lifts the timing sleeve, opening the burst valve. The burst valve is closed when the timing chamber fills at a rate controlled by the orifice. The bypass valve is maintained open by pressure differential across the bypass valve to supply trap reseal flow until the metering valve assembly recloses.
Abstract: The existence of inverted start conditions in a refrigeration chiller is accurately identified by sensing the liquid level in the chiller evaporator. That liquid level is indicative of the location of the chiller's refrigerant charge at start-up. If the sensed liquid level is below a predetermined level, an inverted start condition is verified to exist. Failed starts and chiller system shutdowns are reduced or avoided as compared to systems in which less reliable indicators are used to identify the existence of inverted start conditions.
Abstract: An upper housing shell of a hermetically sealed refrigeration compressor has a central asymmetrical section interposed between a lower cylindrical section and an upper spherical section. The shape of the central section is such that opposite points define a line that is perpendicular to the surface at one point, but is not perpendicular to the surface at the opposite point.