Abstract: Impeller for a radial fan, the impeller comprising a front side, a rear side and a peripheral edge, a hub element, an annular covering disc positioned on the front side, an intake opening formed on the front side, a support disc positioned on the rear side, blades extending substantially radially from the hub element towards the peripheral edge, and outflow openings formed in the region of the peripheral edge. A first outer diameter of a radially outer edge of the annular covering disc is greater than a second outer diameter of a radially outer edge of the support disc. Openings are formed in the annular covering disc, wherein the openings are positioned between the radially outer edge of the annular covering disc having the first outer diameter and a radially inner edge of the annular covering disc having a first inside diameter.

Abstract: Servo gas valve comprising a gas inlet connection, a servo gas connection, a bleed gas connection, a valve body, and first and second valve seats. When a first section of the valve body is pressed against the first valve seat, the gas inlet connection is closed and the servo gas connection and the bleed gas connection are in communication with each other. When a second section of the valve body is pressed against the second valve seat, the gas inlet connection is opened and is in communication with servo gas connection while the bleed gas connection and the servo gas connection are not in communication with each other. The first section of the valve body is configured to allow for self-alignment of the first section of the valve body relative to the first valve seat when the first section of the valve body is pressed against the first valve seat.

Abstract: A gas burner controller adapter for use in adapting a gas burner control device, which is configured to be connected to a flame ionization electrode and a separate ignition electrode, to operate in a gas burner that only includes a single electrode serving as both the flame ionization electrode and the ignition electrode.

Abstract: A gas valve includes a valve seat, a valve stem, a valve body, and a valve diaphragm. The valve body acts together with the valve seat in such a way that the gas valve is in a closed state when the valve body is pressed against the valve seat and the gas valve is in an opened state when the valve body is lifted up from the valve seat. In a partially opened state, a connection between the valve stem and the valve body allows the valve body to tilt relative to the valve stem. The tilt may help provide more stable contact between the valve body and the valve seat when the gas valve is in the partially opened state. This can reduce wear on the gas valve by reducing, for example, valve body bounce.

Abstract: A leakage detection device for detecting water leakage in a water pipe of a water system after a stop valve of the water system is closed. The leakage detection device may be part of a stop valve, and may include an interior chamber connectable to the water pipe in such a way so as to receive a stagnation volume of the water when the water flow through the water pipe is stopped by the stop valve. An actuation element provides a force acting on a diaphragm or a piston in the direction of the first interior chamber and against or into the stagnation volume of water. If water leakage is present in the water pipe, the diaphragm or piston will move under the applied force to compensate for the leakage in the water pipe. A sensor unit may detect water leakage in the water pipe based on the movement.

Abstract: A pressure reducer for a system separator includes a seal element accommodated in a groove, which is subject on a first side to a pressure prevailing at an inlet-side connection stub of the system separator and on a second side to a pressure prevailing in an inlet chamber of the system separator. At least one recess is introduced into a wall delimiting the groove on the first side, into which recess the seal element partially enters, canceling out its sealing effect, when the pressure prevailing at the inlet-side connection stub falls below the pressure prevailing in the inlet chamber.

Abstract: A method for determining an change in an operating condition of a gas burner appliance. In some instances, a calibration of a gas/air mixture may be performed when the combustion quality of the gas burner appliance diminishes. This may be accomplished by adjusting a throttle position of a throttle valve that throttles the gas to the gas burner appliance. After calibration has been performed, a throttle position of the throttle valve is determined, and based on the throttle position determined after calibration, a change of an operating condition of the gas burner appliance is detectable.

Abstract: A pressure independent control valve (10) for controlling the flow of a liquid medium includes a valve body having a side wall defining a conduit that extends from an inlet to an outlet. The side wall of the valve body include a first side opening (23) and a second side opening (24) extending into the conduit. A first insert element (21) is placed into the first side opening (23) and a second insert element (22) is placed into the second side opening (24). At least part of a pressure control device (18) is accommodated by said first insert element (21), and at least part of a flow rate adjustment device (19) is accommodated by said second insert element (22).

Abstract: Fluid flow measuring device for measuring a fluid flow, comprising a rotatable, magnetic element, wherein the rotatable, magnetic element is positioned in the fluid flow, wherein the rotation of the rotatable, magnetic element depends from the fluid flow, wherein the rotation of the rotatable, magnetic element generates a magnetic field; further comprising at least one sensing coil pair having a first sensing coil and a second sensing coil, wherein the respective sensing coils of each sensing coil pair are arranged in such a way that the magnetic field generated by the fluid flow dependent rotation of the rotatable element has a first polarity and a first phase in the region of the respective first sensing coil and a second polarity and a second phase in the region of the respective second sensing coil, wherein at least said polarities differ from each other.

Abstract: In a modulating gas burner, the mixing ratio of a gas/air mixture is controlled over a modulation range of the gas burner by a pneumatic controller. During burner on phases, the combustion quality is monitored via a combustion quality sensor. The combustion quality is used to detect tolerances of the pneumatic controller and/or a potentially changing behavior of the pneumatic controller by checking if the combustion quality is inside or outside a defined combustion quality range. When the combustion quality is inside the defined combustion quality range, the mixing ratio of gas and air of the gas/air mixture is not changed. When the combustion quality is outside the defined combustion quality range, the mixing ratio of gas and air of the gas/air mixture is changed by adjusting a gas throttle to compensate for tolerances of the pneumatic controller and/or for a potentially changing behavior of the pneumatic controller.

Abstract: A method of communication between devices of a building management system (1) over a token ring network, comprising the steps of: a first device receiving (101) the token (2) for the token ring network; the first device, in response to receiving the token (2), broadcasting (105) a request message over the network; a second device, in response to receiving the request message over the network, sending a command message to a receiving device over the network; and the first device passing (107) the token (2) for the token ring network to a subsequent device on the network.

Abstract: Servo gas system (11) for a gas burner (10), namely for controlling a pressure regulation valve (20) positioned in a gas duct (18) of the gas burner, thereby controlling a gas pressure within the gas duct (18) being present downstream of the pressure regulation valve (20) and thereby controlling a pressure difference between a pressure in a burner chamber (12) of the gas burner and said gas pressure within the gas duct (18), the servo gas system (11) comprising a static servo gas flow branch (28) and a dynamic servo gas flow branch (29) being connected in parallel, and a flow sensing element (30) being connected between the static servo gas flow branch (28) and the dynamic servo gas flow branch (29) and providing a signal used to control the pressure regulation valve (20) by an electric actuator (41).

Abstract: An arrangement for managing a liquid medium, such as water, combines a pressure-reducing valve with two backflow prevention valves. Both the pressure-reducing valve and the two backflow prevention valves may be integrated into a common housing, specifically with both backflow prevention valves in an inlet chamber of the housing, wherein the inlet chamber and an outlet chamber of the housing are either fluidly coupled or isolated from one another by the pressure-reducing valve depending on the outlet chamber pressure prevailing in the outlet chamber. In some instances, a manually actuatable shut-off valve may be integrated into the housing. The manually actuatable shut-off valve may selectively keep the pressure-reducing valve in a closed position or allow the automatic opening and closing of the pressure-reducing valve depending on the outlet chamber pressure prevailing in the outlet chamber.

Abstract: A regulating device may include a housing that defines an inlet chamber and an outlet chamber, with a flow restriction seat between the inlet chamber and the outlet chamber. A flow restriction valve is movable relative to the flow restriction seat to adjust the flow between the inlet chamber and the outlet chamber of the regulating device. A servo valve having a servo chamber may be used to adjust the position of the flow restriction valve. The servo chamber may be fluidly coupled to the inlet chamber though a fixed flow restriction and to the outlet chamber though an adjustable flow restriction. A stepper motor may be used to adjust the servo valve to adjust the adjustable flow restriction between the servo chamber and the outlet chamber. This causes a change of the servo pressure, which moves the flow restriction valve and adjusts the flow of the regulating device.

Abstract: A regulating device may include a housing that defines an inlet chamber and an outlet chamber, with a flow restriction seat between the inlet chamber and the outlet chamber. A flow restriction valve is movable relative to the flow restriction seat to adjust the flow between the inlet chamber and the outlet chamber of the regulating device. A servo valve having a servo chamber may be used to adjust the position of the flow restriction valve. The servo chamber may be fluidly coupled to the inlet chamber though a fixed flow restriction and to the outlet chamber though an adjustable flow restriction. A stepper motor may be used to adjust the servo valve to adjust the adjustable flow restriction between the servo chamber and the outlet chamber. This causes a change of the servo pressure, which moves the flow restriction valve and adjusts the flow of the regulating device.

Abstract: The invention relates to a gas regulating unit with a valve basic body (11) which forms at least one gas inlet chamber and one gas outlet chamber, with a safety valve and with a main gas valve, wherein the safety valve and the main gas valve either open or close a gas flow from the gas inlet chamber into the gas outlet chamber.

Abstract: Method for operating a gas burner, wherein a gas/combustion air mixture is fed to the gas burner for combusting in said gas burner in such a way that a combustion air flow, which is inducted by a fan, is mixed with a gas flow and the resulting gas/combustion air mixture is fed to the gas burner, wherein to this end a control device, on the basis of a control deviation between an actual value, which is recorded by a sensor providing an electrical or electronic measurement signal and acting on a gas line which carries the gas flow, and a corresponding reference value, determines a manipulated variable for a gas valve which influences the gas flow, wherein the gas valve is adjusted in dependence upon this manipulated variable in order to make available to the gas burner the gas/combustion air mixture with a desired gas/combustion air ratio, and wherein the control device alters the gas/combustion air ratio of the gas/combustion air mixture in dependence upon a rotational speed of the fan in such a way that at re

Abstract: The invention relates to a device for providing a gas/combustion air mixture for a gas burner, comprising a fan (11) for providing a combustion air flow, a gas control device for providing a gas flow and a mixing device (13) for mixing the combustion air flow and the gas flow, thus providing the gas/combustion air mixture. Said mixing device (13) and the fan (11) are connected together on one side, and on the other side, the mixing device and the gas control device are connected together. According to the invention, the mixing device (13) and the fan (11) are connected together in such a manner that a vibration absorber (15) is arranged between a connecting section (12) of the mixing device (13) and a connecting section (10) of the fan (11).

Abstract: An illustrative method for operating a valve, where the valve includes a valve seat, a valve plunger and a stepper motor for moving the valve plunger from a first position into a second position in which the valve plunger is pressed against a valve seat and for compressing a flexible element assigned to the valve plunger in said second position. The stepper motor may be driven a defined number of steps (NTOTAL) in order to move the valve plunger into the second position and to compress the flexible element. The method may include: driving the stepper motor a first number of steps (N1) at a first current level (I1); driving the stepper motor a second number of steps (N2) at a second current level (I2); and driving the stepper motor a third number of steps (N3) at a third current (I3) level.

Abstract: Regulating device for gas burners for providing a gas/air mixture, with a mixing device for mixing a gas flow with a combustion air flow to provide the gas/air mixture, wherein at least one gas valve is positioned in a gas line which conducts the gas flow, which is adjusted in dependence upon a measurement signal of an electric or electronic sensor, wherein the sensor determines the differential pressure between the gas line and a reference pressure. The mixing device may be formed as a Venturi nozzle, in which the gas flow and the combustion air flow are mixed, wherein the reference pressure for the sensor is a device in which the reference pressure prevails, and the device is connected via a connecting line to the Venturi nozzle downstream of the mixing region of the Venturi nozzle.