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  2. HVAC control system - Wikipedia

    en.wikipedia.org/wiki/HVAC_control_system

    HVAC (Heating, Ventilation and Air Conditioning) equipment needs a control system to regulate the operation of a heating and/or air conditioning system. [1] Usually a sensing device is used to compare the actual state (e.g. temperature) with a target state. Then the control system draws a conclusion what action has to be taken (e.g. start the ...

  3. Damper (flow) - Wikipedia

    en.wikipedia.org/wiki/Damper_(flow)

    A damper is a valve or plate that stops or regulates the flow of air inside a duct, chimney, VAV box, air handler, or other air-handling equipment. A damper may be used to cut off central air conditioning (heating or cooling) to an unused room, or to regulate it for room-by-room temperature and climate control - for example, in the case of ...

  4. Run-around coil - Wikipedia

    en.wikipedia.org/wiki/Run-around_coil

    A run-around coil installation, serving air handling units on the roof of an office building. A run-around coil is a type of energy recovery heat exchanger most often positioned within the supply and exhaust air streams of an air handling system, or in the exhaust gases of an industrial process, to recover the heat energy.

  5. Reversing valve - Wikipedia

    en.wikipedia.org/wiki/Reversing_valve

    Reversing valves are built into the heat pump by the manufacturer, and must be replaced by an HVAC technician if they fail. Since the valve is an integral part of the sealed refrigerant circuit, proper procedures for recovering and then later refilling the refrigerant must be followed, to prevent its loss into the atmosphere.

  6. Automatic balancing valve - Wikipedia

    en.wikipedia.org/wiki/Automatic_balancing_valve

    Overflow in a circuit is costly. Traditional control valves make it inevitable. As we size a control valve, the K v calculated almost certainly will not match the K v of the nearest appropriate valve. For example, a K v calculation of 4.5 m 3 /h would most likely lead to the selection of a valve with a K v = 6.3 m 3 /h. This means the valve is ...

  7. Valve actuator - Wikipedia

    en.wikipedia.org/wiki/Valve_actuator

    The blue valve body is visible in-line with the pipe. The valve actuator opens or closes the butterfly disc of the valve based on electrical signals sent to the actuator. Another valve actuator is visible in the background, with windows to indicate the valve position. A valve actuator is the mechanism for opening and closing a valve. Manually ...

  8. Control valve - Wikipedia

    en.wikipedia.org/wiki/Control_valve

    A control valve is a valve used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller. [1] This enables the direct control of flow rate and the consequential control of process quantities such as pressure , temperature , and liquid level.

  9. Heat pump and refrigeration cycle - Wikipedia

    en.wikipedia.org/wiki/Heat_pump_and...

    Thermodynamic heat pump cycles or refrigeration cycles are the conceptual and mathematical models for heat pump, air conditioning and refrigeration systems. [1] A heat pump is a mechanical system that transmits heat from one location (the "source") at a certain temperature to another location (the "sink" or "heat sink") at a higher temperature. [2]