Johnson Controls A28MA-2 2-SPDT Temperature Control 40°F-120°F Rainproof 6" Capillary

The Johnson Controls A28MA-2 is a two stage remote bulb capillary thermostat used in HVAC systems. It has an outdoor weatherproof housing and a capillary tube that measures temperature from a remote location from the main body of the thermostat. This thermostat comes on the heating system when the temperature around it rises to the levels below the minimum that has been set (40°F). Conversely, when it gets to the upper limit (120°F), the cooling system is initiated. This two-stage operation makes the control of temperature better than single-stage thermostats and also save energy.