Energy-optimized automation for ventilation and air conditioning in energy-efficient buildings

Intelligent energy saving functions

Intelligent energy saving functions for ventilation and air conditionings – tested under practical conditions – prevent unnecessary energy usage.

AirOptiControl – energy efficiency thanks to optimized air volume flow

This modular designed application offers a number of function variants for the control of air handling plants or for optimum fan operation.

AirOptiControl optimizes the volumetric air flow, thus providing an excellent basis for energy-efficient operation of ventilation and air conditioning systems. At the same time, comfort control ensures adherence to the boundaries of temperature, indoor air quality, and humidity.

AirOptiControl is suited for individual room systems or several zones and also  controls basic load heating.

tx2 Economizer – energy-optimized control of air conditioning plants

The Economizer tx2 application offers energy-optimized air conditioning plant control by conditioning the air supplied to the rooms using the most favorable form of energy.

The patented procedure continuously calculates air conditioning costs, allowing for targeted selection of the most favorable method.

Optimization can be based on energy, costs, or CO2. As a result, Economizer tx2 helps lower energy costs and offers an excellent basis for highly efficient operation.

Air flow control – reduction of air flow saves energy

If there is a need to throttle or shut off individual sections of a branching duct network without affecting other operational systems, the supply air duct must be maintained at a specific pressure.

To achieve this, a modulating controller compares the pressure difference against the setpoint. In case of a deviation, the controller corrects the delivery pressure of the fan by changing the rotor speed.

The reduction of air flow saves energy for air handling and distribution.

Supply air temperature control – reduction of energy input

A control loop enables to control the supply air temperature. The setpoint is defined as a function of the loads in the room. This can normally only be achieved with an integrated control system, enabling to collect the temperatures or actuator position in the different rooms.

Energy savings are achieved as the supply air temperature is controlled depending on the largest individual load of all individual rooms. This reduces the number of individual room temperature controllers that reheat in the summer or recool in the winter.

Humidity control – resulting in lower energy consumption

Direct humidity control is used in cases where the setpoints for temperature and humidity of the conditioned space must be maintained exactly at all outside air states and in case of internal heat gains and external humidity.

Energy savings result as supply air or room air is cooled, humidified and reheated to the extent required.

Heat recovery control – unnecessary recooling reduces energy consumption

Heat recovery equipment in ventilation systems can help save considerable amounts of energy. The air conditioning process is controlled in sequences. This means that, first, the maximum amount of heat is recovered and only then will the heating or cooling sequences be activated.

During periods where the effect of the heat exchanger will no more be benefical, a control loop between "stops" and "modulates" or bypass the heat exchanger is needed. Temperature sequence control at heat recovery prevents unnecessary recooling of the supply air.

Air side icing protection control – no increase of air pressure

If the extract air temperature falls below the dew point at outside temperatures below freezing, ice forms on the extract air side of the heat exchanger, constricting the flow area.

This occurrence must be prevented by protective equipment. The power of the exhaust air fan need not be increased with icing protection limitation control. This leads to energy savings.

Free cooling – H,x-directed control to save energy

With the H,x-directed control function, the amount of outdoor and recirculation air are modulated during all periods of time to minimize the amount of mechanical cooling.

The energy savings are achieved thanks to Maximum Economy Changeover (MECH): Heat recovery is opened whenever exhaust air enthalpy is lower than outdoor air enthalpy, reducing energy demand on active cooling of supply air.

Filter control – Saving energy with constant monitoring

In variable air flow volume systems, flow volume control keeps the air flow volume constant in spite of increasing clogging by increasing the fan speed accordingly. If the system is operated with a reduced air flow volume, the fans are run at a disproportionately high speed until the filter monitor is triggered, which consumes energy unnecessarily.

This can be avoided with a filter control via a differential pressure sensor with compensation for filter clogging based on the current air flow volume.