Temperature controller, changeover with heating/cooling switch, R.1/R.3, polar white, gl. Temperature controller with central piece, rocker switch, imprint, control knob with temperature range limitation, adjustable temperature control range, temperature measurement via internal temperature sensor. For heating or cooling operation, e.g. for actuators closed when de-energized, with thermal feedback, without spreading claws, with plug-in terminals. When the set temperature is reached, the contact changes. Note: Neutral conductor required! Suitable for systems with heat pumps.