Solar thermal systems are managed and operated by solar controllers.

As soon as the temperature of the collector exceeds the store temperature, the controller activates the circulation pump and the heat medium liquid transports the heat, taken up at the collector, into the hot water store (constant differential temperature regulation).

Conventional heating systems ensure a required after-heating within the store. Because of the easy integration into building techniques and an average life expectation of more than 30 years, solar systems are an ideal complement to modern heating technology. RESOL differential temperature controllers are used in solar, heating and air-conditioning systems to initiate switching processes depending on thermal, hydraulic and environmental conditions.

In general, the controller monitors the determined temperature differences of the sensors and compares them to the given set temperature differences. The controller is switched on if the adjusted temperature difference is exceeded. The system is controlled by one or more relays. Pumps or electric valves may be connected to these relays. Precision temperature sensors are used for measuring purposes. Those sensors are available in various mechanical versions and are interchangeable.

Apart from these basic functions RESOL controllers offer a variety of options including the well-known user-friendly mounting and operation facility.