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A thermostat is a regulating device component which senses the temperature of a physical system and performs actions so that the system's temperature is maintained near a desired setpoint.
Thermostats are used in any device or system that heats or cools to a setpoint temperature, examples include building heating, central heating, air conditioners, HVAC systems, water heaters, as well as kitchen equipment including ovens and refrigerators and medical and scientific incubators. In scientific literature, these devices are often broadly classified as thermostatically controlled loads (TCLs). Thermostatically controlled loads comprise roughly 50% of the overall electricity demand in the United States.A thermostat operates as a "closed loop" control device, as it seeks to reduce the error between the desired and measured temperatures. Sometimes a thermostat combines both the sensing and control action elements of a controlled system, such as in an automotive thermostat.
The word thermostat is derived from the Greek words θερμός thermos, "hot" and στατός statos, "standing, stationary".

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  1. A

    Room Thermostat: Would I Benefit From Optimum Start/Stop?

    Hi, I just moved into a new house and it has a Glow Worm Compact 24c combi boiler and a ESI ESRTP4RF+ programmable room thermostat and I am wondering if it's worth turning on the optimum start and stop features? There is also something called TPI (chronoproportional control) but I'm not sure how...
  2. G M

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  3. A

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  4. stumac

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  5. D

    How do I wire up this Honeywell T3R Thermostat?

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  6. R

    Warmflow B1 Thermostat Control

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  7. S

    How do I remove this radiator thermostat?

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  8. A

    Difference between VRT 380f and VRT 380f/2 Vaillant controllers?

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  9. spagettilegs

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  10. D

    Choice of thermostat advice please

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  11. U

    Does anyone's heating actually work as intended with thermostat?

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  12. G

    Polypipe Programmable Room Thermostat - PB PZP

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  13. Uncle Nick

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    Hi all, as it’s starting to get chilly at night, we’re thinking of having the heating on at night… well the wife is. Which led me to wonder whats the point of having a room stat when the radiators all have their own thermostat controls? We currently have just a time controller for the heating...
  14. C

    Main combi 30 HE Safety thermostat

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  15. R

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  16. X

    Vaillant VRT 392 Thermostat (wired) not working

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  17. T

    Danfoss HTS3 HW tank thermostat

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  18. V

    Bathtub mixer with thermostat- lost water pressure

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  19. G

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  20. T

    Improvements for pre-lagged DHW cylinder

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