An HVAC system and method for characterizing a chosen VAV valve involves measuring the valve's volumetric flow rate versus valve position at just one or at some other limited number of data points and comparing that to the average characteristics a rather large group of similar valves. A custom characterization of airflow versus valve position for the chosen VAV valve is then created based on a difference between the characteristics of the chosen valve and that of the group of valves. In some examples, the VAV valve is of a venturi style such that a generic characterization of the group of valves is substantially linear when their flow rates are expressed logarithmically.

A pilot-operated relief valve assembly can include a relief valve, and a pressure detection assembly. A valve lift factor or indicator of relief flow can be determined based on pressure measurements gathered by the pressure detection assembly.

A diagnostic apparatus for a coolant control valve including a housing having a plurality of ports, a valve member provided to be rotatable in the housing, and a driving device rotating the valve member between two end positions, the diagnostic apparatus including at least one position sensor provided on an external surface of the housing for sensing a position of the valve member, a determination device for determining whether or not the valve member is stuck using the position of the valve member sensed by the position sensor and a controller for controlling the driving device.

A pilot-operated relief valve assembly can include a relief valve, and a pressure detection assembly. A valve lift factor or indicator of relief flow can be determined based on pressure measurements gathered by the pressure detection assembly.

The invention relates to a method for determining a characteristic value of a magnetic switch valve. The magnetic switch valve can be switched from a closed switch state into an open switch state, via the movement of a rotor by means of a switching magnet applied with current against a conservative restoring force. According to the invention, during the switching of the switch valve from the open state into the closed state, the time course of the current flowing through the switching magnet and/or of the voltage at the switching magnet is measured. The characteristic value to be measured is evaluated from this time course. It was recognised that every movement of the rotor against the switching magnet induced a voltage in same. Now the voltage at the switching magnet is regulated at a constant value, for one, the voltage induced by the movement can be observed as a control deviation in the short term. For another, the induced voltage causes a current flow through the switching magnets. Based on this, the kinematics of the rotor can be deduced. Given that the switching magnet has an ohmic resistance, energy is also dissipated via the current flow. This energy is the key to determining the switching path covered by the rotor when switching between the closed and the open state. The invention also relates to a measuring device that is particularly suitable for the method.

This invention provides two methods for detecting mechanical or electrical faults in a solenoid valve. In the first method, a force sensor is placed in the valve in such a way as to detect changes in the impact force of the plunger against the solenoid valve body or coil housing (depending upon the direction of movement of the plunger upon application of the electric current/magnetic field). A second method is provided which makes use of an accelerometer placed in such a way as to detect changes in the response of the plunger to the application of the magnetic field.

In accordance with the resent invention, there is provided a fugitive emission detection system for use in conjunction with a valve having a packing deign which includes a primary packing and a secondary packing. The valve further includes a leak port which is disposed within the valve bonnet between the primary and secondary packings. The detection system is operative to maintain the leak port in a normally open state. As a result, any fluid leakage past the primary packing is normally sent to the detection system, as opposed to being applied to and thus pressurizing the secondary packing. In the event of that a prescribed level of fluid leakage beyond the primary packing is detected, the leak port will be closed. The closure of the leak port facilitates the pressurization of the secondary packing.

A pressure regulator for liquid media includes a through-flow path which extends between two connections for a medium-conducting line. The through-flow path is equipped with a valve seat which can be released or closed by a closing element that is mounted in a movable manner between a closing position and a release position. A wear of the closing element and/or the valve seat can be monitored during ongoing operations using a wear sensor device.

A system, method, and an apparatus relating to data collection regarding valve movement over a period of time in order to determine the effects of stiction on the valve. With data collection done over a period of time, it is possible to remove dependency on a high speed method of data collection. The evaluation of the valve movement includes consideration of a manipulated variable (MV) for diagnosis, or detection, of stiction of the valve.

A venting and/or bleeding valve with a valve housing, a main valve arranged in the valve housing for rapid venting and bleeding of piping connected to the valve housing, an auxiliary valve arranged in the valve housing for operating ventilation of the piping at operating pressure, and a float arranged within the valve housing and controlling the main valve and the auxiliary valve as a function of the filling level of a fluid located in the valve housing. The venting and/or bleeding valve contains a valve position sensor for acquisition of the position of the main valve, at least one additional sensor for acquisition of the humidity and/or the pressure and/or of the temperature in an interior space of the valve housing, and an evaluation unit for acquisition of an operating state of the venting and/or bleeding valve as a function of the values acquired by the valve position sensor and any additional sensor.