“Ventilation Systems” presents the A21 – a new ventilation management system for the company’s air handling units, which has been developed, based on extensive market research and the feedback from our customers.

The A21 control system is the first representative of a new generation of control systems designed to replace a number of outdated controllers including A11, A14, A19, and the Carel units (A17 and A18). The control system provides a common platform for the entire range of VUT and VUTR air handling units and the DVUT single-room units.

Unlike other control systems the А21 has a much wider range of functionality. First and foremost, it is Wi-Fi connectivity that immediately sets this control system apart from its predecessors. This feature enables a wireless connection between an air handling unit and a smartphone running a Vents AHU mobile application with a host of advanced settings or to А22 or А25 wall-mounted control panels.

To control the unit from anywhere in the world all you have to do is connect it to a wireless network and synchronise with Vents Cloud Server. The cloud server enables the company maintenance engineers to access the air handling unit status details and the alarm logs for a professional evaluation of the unit health and take quick remedial action, if necessary.

The new control system takes unit automation to a next level. This includes activation and deactivation delay settings and a user-defined weekly schedule. The weekly schedule enables setting the air handling unit speed, operation times, and the temperature threshold for their activation. That being said, the settings can be applied to every day, an entire week, weekdays or weekends. With the А21 automatic control system you can choose among the four basic operating modes: ventilation, heating, cooling or auto (in this mode the unit automatically provides air heating or cooling as necessary). You can use the seekbar for stepless speed selection or choose one of the pre-sets.

The А21 automatic control system allows high-precision air quality control including humidity level, CO₂ content, concentration of volatile organic compounds (VOC) such as cigarette smoke and household vapours as well as the content of ultra-fine particles (PM2.5) such as allergens and particulate matter. To implement the air quality control functions the А21 control systems must be additionally fitted with СО₂, VOC and PM2.5 sensors to complement the standard humidity sensor built into the system.

The new automatic control system is compatible with building management systems (BMS) commonly known as “smart home”. The automatic control system connects to other electronic devices over an RS-485 serial data link using the Modbus open communications protocol. The RS-485 data link supports up to 16 simultaneous air handling unit and up to 16 simultaneous control panel connections.

The А21 control system offers improved malfunction identification accuracy with error code and description displayed via the mobile application or on the А25 control panel screen.  The system also has a special timer for observing filter replacement intervals. In units equipped with a pressure switch the filter replacement signal depends on the actual contamination of the filters.

The А21 system controls the implementation of the freeze protection protocols. The three freeze protection methods include periodic shutdown of the supply fan, opening the bypass and activation of the electric pre-heater. The bypass also provides air cooling during the warm season.

A special engineering menu enables setting the operation parameters which are not available from the basic menu and are not accessible via other control systems. The engineering menu, which is strictly recommended for experts only, extends the system capabilities even further. In particular, this menu contains pre-set values for the basic speeds (1, 2, and 3), advanced temperature settings and those of the external sensors, the data reset feature and much more. The engineering menu also enables the “Fireplace” mode in which the speed of the supply and the exhaust fans is adjusted individually. This function provides improved fire safety by cutting out the supply of air, which may sustain combustion, and boosting the exhaust fan speed for more effective smoke extraction thus preventing a potential fire.

The А21 automatic control system is a state-of-the-art high-tech ventilation management solution which adds simplicity and convenience to ventilation unit operation with a notable improvement in functionality.