Synco is a versatile and modular range of controllers from Siemens for applications in the field of heating, ventilation, air conditioning and refrigeration (HVAC).
All types of Synco controllers offer built-in energy saving features and provide optimum preconditions to ensure compliance with energy efficiency class A. This means that, for example, a cost and energy efficient HVAC control system can be installed and set up without the need for programming.
The relevant functions can be activated without programming on existing plants also. Synco controllers have integrated building and room automation features. Energy savings and CO2 reductions can be achieved without compromising on indoor comfort.
The importance of energy-efficient products in building automation and the resultant huge saving potential are demonstrated by the fact that buildings worldwide consume about 41% of primary energy, 85% of which is required for space heating and cooling. For this reason, Siemens place emphasis on energy-saving products, including the standard HVAC controllers.
In addition to the classical application-specific functional units, the modular Synco controllers of the 700 series provide energy saving features conforming to EN 15232, and can be configured or activated at the time of commissioning. These are energy saving functions implemented in the range of ventilation controllers (Synco RMU) and heating controllers (Synco RMH and RMK). A brief description is given below:
- Demand-controlled ventilation
- Heat recovery
- Night cooling
- Optimisation of heating circuit control
- Quick setback of heating circuit
- Demand-based production of heating and cooling energy
The fan and the air handling processes such as heating, cooling, humidification and dehumidification are the major energy users in ventilation and air conditioning plants. For this reason, the fan should be switched off whenever possible and operated only when there is a demand for ventilation resulting from inadequate indoor comfort conditions, using the lowest possible fan speed.
Switching on the fan and increasing the amount of outside air delivered to the space takes place through demand-dependent control (by means of indoor air quality (IAQ) sensors for acquiring CO2/VOC), presence-dependent control (with the help of presence detectors) or resulting from the sustained mode function for controlled variables such as temperature and humidity. The process runs until the required operating state is reached. Then, the plant is shut down again.
Heat recovery equipment in ventilation systems can save energy. The heat recovery process is controlled in sequences. This means that, first, the maximum amount of heat is recovered and only then the heating or cooling sequences are activated. In addition, the operating action of the heat recovery equipment is adapted on the basis of a comparison measurement of extract air and outside temperature. The efficiency of heat recovery is monitored to ensure that in the event of a failure, the lack of supply by the heat recovery equipment will not be compensated for by the air heating or air cooling coil, which leads to extra energy consumption. If the efficiency drops below a certain limit, a fault status message is delivered.
During the night when the rooms are not normally occupied, they are cooled down with cool outside air. Expensive generation of cooling energy during the day can thus be minimised. Night cooling is activated through a comparison measurement of outside and room temperatures, and remains in operation until the required switch-off temperature for the room is attained.
The objective of optimum start control is to reach the Comfort or Pre-comfort set point at the beginning of the scheduled occupancy period. For that purpose, the heating circuit is switched on for a certain period of time before occupancy starts, depending on the outside temperature. If a room temperature sensor is installed, the controller also takes into consideration the room temperature when calculating the forward shift. If no room temperature sensor is available, the optimisation functions use a room model, which calculates the required room temperature based on the outside temperature, the building time constant and the rate of room temperature.
Optimum stop control switches off the heating circuit as early as possible to ensure that the room temperature lies below the Comfort or Pre-comfort set point when the change from Comfort or Pre-comfort to Economy mode is made. Optimum stop control can be provided only if a room temperature sensor is present. When the room operating mode changes from Comfort or Pre-comfort to Economy or Protection, quick setback is activated, the heating circuit pump is switched off, and the mixing valve is closed. The heating circuit remains shut down until the required room temperature is reached. As a result,
the number of operating hours for the pump is reduced. The function ceases when the room temperature reaches the new set point, or when the room operating mode changes to Comfort or Pre-comfort.
A heating boiler or refrigeration machine should operate only when there is a demand for heating or cooling energy. Based on the information received from the heating, cooling or DHW zones, the Synco controllers automatically exchange data through the KNX bus. Using this information from the zones, the controllers calculate the required set points and switch on the respective heating or cooling sources depending on the demand. This makes certain that aggregates or pumps do not constantly operate, thus minimising the number of operating hours.
With the integrated energy saving features provided by the standard HVAC controllers, Siemens offer benefits in terms of cost savings and environmental protection. As a result, HVAC applications can be planned without effort, focusing on energy efficiency right from the start. Straightforward activation of the energy saving functions optimises operation and increases the value of the plant.
All energy saving features are targeted at demand-based operation of the HVAC plant and ensure adequate indoor comfort levels for users of the buildings or the individual rooms.