Central heating system temperature controller TECH ST-21 is a microcontroller steering with LED display to control the water circulation pump of a central heating installation.

Central heating system temperature controller main task is to turn on a circulation pump when the central heating boiler temperature setpoint is reached and turn it off when the temperature drops below the given temperature setpoint.

Using the central heating system controller despite the convenience is an economic pump operation benefit, allowing to save electricity, in the same time extending the pump lifetime and its reliability (less mechanical operation of pump parts).

Temperature regulator ST-21 may also act as thermostat, that stops pump operation after reaching the temperature setpoint.

The temperature controller provides also ANTISTOP function, which prevents pump blocking outside season (the pump runs approx. every 10 days for 1 minute).

An additional security feature is ANTIFREEZE, which prevents water freezing in the central heating system when the temperature drops below 6 °C (the pump will run permanently).

Functions performed by the central heating temperature controller

• Handling circuit pump C.O
• The ability to work as a thermostat
• ANTISTOP function preventing water stagnation
• ANTIFREEZE function preventing water freezing

Central heating temperature controller

• Controller steering
• Central heating temperature sensor