Stemco Capillary Switch 

HVAC Temperature Control

Temperature switches found in HVAC systems are typically mechanical controls that are based on physics. More times than none, most HVAC systems have a requirement for these controls rather than an electronic type controller because failure modes are limited versus an electronic control. Rather than an electronic controller using inputs/outputs to communicate with the HVAC equipment, our temperature switches react to change in the environment causing the equipment mode to change as a reaction. For more information on how Capillary Switches are used in industrial applications, click on one of the articles below. 


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.


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.

Custom options

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

made in the u.s.a

Products are designed, manufactured, tested and shipped from Senasys’ facilities in Eau Claire, WI to clients across the globe.


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