STEMCO Capillary Switch

Capillary Switches Controls Water Heater Temperatures

Capillary Switch Senses Liquid Temperatures

Most commercial style dishwashers, and even a number of household type dishwashing appliances, use one or two capillary switches to heat the water.

Capillary Switch in Hot Water Application

                          Click to Enlarge

The capillary switch’s bulb will be immersed directly into the water or contained within a thermowell, which controls a series of heating elements in either a fixed temperature style or an adjustable range style.  When the water heater is turned on the capillary, bulb or probe, senses the temperature and turns on the elements. When the calibrated temperature of the capillary switch is reached it turns off the heater until the water temperature is cooled to a pre-set or calibrated temperature; and then the process starts all over.

A second capillary would be used as a limit to prevent the heaters from going into a runaway condition and overheating the system. This second limit capillary could be a manual reset, which requires human intervention to restart, or automatic allowing the system to operate under normal conditions once the temperature has dropped.

This same design is used to heat or cool many other fluids such as food grade oils, lubricants, chemicals and solvents. The better quality capillary thermostat switches, such as ours, can be ambient temperature compensated. The less expensive ones are not.

To view our standard thermostat options, visit our website.

For more information about our thermostat switches contact our direct support at 715-831-6353.

Learn more about our thermostat switches. Contact us about thermostat switches.