Capillary Style Thermostat Switch

A Liquid expansion capillary thermostat uses expanding liquid to open or close contacts in response to temperature changes. No matter which style or model you choose, all of the liquid expanding capillary thermostats operate using the same physics. A fluid is encapsulated in a metal tube (bulb and capillary) and when the temperature changes the fluid either expands or contracts. This fluid change moves the head which triggers a snap action switch either opening or closing the circuit.

The bulb is typically a larger diameter tube mounted in the material flow being sampled. The capillary is a small tube that carries the fluid away from the bulb to the head. The head can be a diaphragm or bellow, which moves with the changing temperatures.

Our liquid expansion capillary thermostats also offer the option of being ambient compensated to offset the differential in temperature which keeps our thermostat controls more accurate as it’s environment changes.

Products are designed, manufactured, tested and shipped from Senasys’ facilities in Eau Claire, WI to clients across the globe. Senasys takes pride in quality control and reliable operation of our products. Every switch is individually 100% tested before it leaves the plant. Our capillary thermostats are UL & cUL approved.

More information about capillary thermostats.

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Bulb & Capillary Thermostats

Original equipment manufacturers worldwide use thermostat switches designed and manufactured by STEMCO, a Division of Senasys. No matter which style or model you choose, all of the capillary thermostat switches operate using the same physics. A fluid is encapsulated in a metal and when the temperature changes the fluid either expands or contracts. This fluid change moves a diaphragm which is in touch with a snap action switch and either opens or closes a circuit.

Ambient Compensation

Our capillary thermostats can be ambient compensated to offset the differential in temperature which keeps our thermostat controls more accurate as it’s environment changes.

Custom Options

Capillary thermostat switches built by Senasys can also be built to customer specifications. This insures you get the exact control you want without paying for features you don’t need.