Capillary thermostat for water heaters


Capillary thermostat for water heaters

In Capillary thermostats temperature sensor consists of probe, capillary tube, diaphragms and expansion medium. When the sensor is heated, the liquid medium heats up and expands. The expansion of the medium increases in the closed-circuit system.

The pressure increase is converted into displacement in the diaphragm. This displacement, also called travel, actuates a snap-action switch, which opens or closes the contacts in the electric circuit.


The reference variable is set via the thermostat’s capillary adjusting spindle. Capillary thermostats are widely used to control air and water temperature thanks to their precision and and flexibility of installation

Thermowatt has always been synonymous of thermostat and it is well-known all over the world for for the quality, safety and reliability of its products.

Specific know-how in experimenting with materials, long experience in producing and controlling heating and the most advanced laboratory in the  field have enabled Thermowatt to achieve numerous patented technical solutions.

Thermowatt thermostat, an extremely thermosensitive with guaranteed reliability, is manufactured with an assembly process that uses the most modern technologies and a specific system to manufacture and anchor the circuit.

Thermowatt thermostats are realiable, safe and innovative, for this reason they are among the most used worldwide in hot tank, electric and solar water heaters.

Standardized production, computerized thermostat calibration processes and rigorous controls allow Thermowatt to ensure an excellent level of quality and reliability of its products using mass production processes according to the certificates issued by the most prestigious international  institutes

four pillars, for constantly evolving ideas.

& Experience

After 50 years of developing high quality electric heating elements and thermostats we reached a unique know-how.

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Continuous investments and listening to the customer needs are key to a company policy aimed at constant innovation.

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360° Support

Our support starts during the product design and goes on, step by step, till the after-sale.

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Quality, Reliability and Safety

Our Full Reliability Approach guarantees best in class products certified by the major international institutes.

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