If you need more control than just a thermostat can give but don’t need a full-blown communicating DDC system, The RWD Universal Controllers from Siemens Building Technologies could be just what you’re looking for. This series of controllers is intended for heating, air conditioning, ventilation and refrigeration in HVAC control applications. The RWD controller combines that highest standards in HVAC control performance with simple operation and monitoring of all inputs and outputs.
Installation and commission are easy with the pre-programmed applications for temperature, static pressure, humidity, air pressure, fluid pressure, refrigeration, air quality and air fluid velocity control. Auxiliary control functions include day/night setpoints, remote setpoint control, limiter control, cascade control, maximum priority, setpoint reset, and Summer/Winter operation. Control parameters can be adjusted via three buttons on the face of the device or with a laptop computer and program software.
See the attached .pdf for more information and technical documentation: Siemens RWD.