Jun 24

Energy Efficiency through Ventilation, Heating and Air conditioning systems

  • June 24, 2014

On June 18th, 2014 a seminar was held in the headquarters of “TANGRA” focusing on “Energy Efficiency through ventilation, heating and air conditioning systems”. More than 80 engineers and specialists in the field of HVAC attended the event.

Енергийна ефективност 3 - 1
The presentation began with an overview of the policies and norms of the European Union and Bulgaria that target energy consumption reductions. Dipl. Eng. July Armianov, owner and general manager of TANGRA, presented the legal requirements for mechanical ventilation installations in buildings within the European Union, UK and USA. After demonstrating best practice in these geographical areas, the Bulgarian standard (BDS) was also explored, which states that all installations that have a fresh air supply and dirty air exhaust features, must have energy recovery systems. Exceptions are allowed only in cases, where huge amounts of heat are available and there is no room or systems to recover it.

The factors used to calculate the energy efficiency of ventilation systems were presented: specific fan power (SFP), air speed variation in the different sections of the air handling units and the heat exchanger energy recovery classes. Dipl. Eng. Armianov gave special consideration to the importance of paying particular attention to the specifics of heat recovery systems during their selection. He presented the important relationship between capital investment, operating time, the climate the system operates in, primary energy, maintenance costs, financial support from the government and last but not least, the change in the market value of the site as a function of the set “extras”.

This was followed by a presentation of the software used to select plate heat exchangers and heat recovery ventilation. TANGRA has developed a free specialized software to help calculate and select energy saving ventilation systems. The software can be found on the company website and allows the user to make calculations for standard efficiency systems as well as the systems with increased efficiency.

Енергийна ефективност 3 - 2
The presentation continued with the family of air handling units, produced by TANGRA. The range is called TANGRA AHU. It is fully certified by TUV Rheinland and is divided into four segments:
– Air handling units which supply fresh air only or which have a mixing section
– Air handling units with heat recovery
– Hygiene air handling units
– Air handling units with incorporated heat recovery and heat pump module

Specific focus was drawn to the hygienic version of air handling units as well as the one with a heat pump module. The applications for the hygienic air handling units include not only the healthcare sector (hospitals, operation theaters, ER) but also the pharmaceutical sector, the food and beverage sector as well as specific productions. Hygienic air handling units produced by TANGRA – TANGRA AHU HYG are certified to the standards EN 13053, DIN 1946-4, VDI 6022 and VDI 3803.

In the range of air handling units with heat pump module, TANGRA presented the two modifications TANGRA AHU DEX M and TANGRA AHU DEX S. The energy consumption and efficiency of both models was discussed with Dipl. Eng. Armianov, outlining the advantages of these units such as the lack of external piping, high static pressure, EC fans, inverter compressors, the lack of defrost and last but not least, the TUV Rheinland certification.
In the last part of the presentation, Ivan Armianov MSc. – Commercial Manager, presented the new control systems for heat recovery ventilation. “TANGRA” has developed a control called TANGRA Smart, which allows the system to be operated remotely through a smart phone, tablet or from a PC. TANGRA Smart allows the user to control heat recovery ventilation systems with a pre-heater, additional electrical or water heater and as an option – a cooling coil for summer mode.

The seminar came to an end with a networking event where guests were given the opportunity to view and touch the products, presented by TANGRA.



Енергийна ефективност 3 - 3






Енергийна ефективност 3 - 4


Енергийна ефективност 3 - 5


Енергийна ефективност 3 - 6


Енергийнна ефективност 3 - 7


Енергийна ефективност 3 - 8


Енергийна ефективност 3 -9

This is the third seminar, which “TANGRA” held under the topic “Energy efficiency through HVAC systems”. In 2012 we launched the series with the first seminar entitled “Heating with pellets” at which the ranges of pellet boilers “TANGRA CL” and “TANGRA HP” were presented. In 2013, at the event “High efficiency heat recovery ventilation”, TANGRA brought together the Bulgarian Chamber of Architects and the Chamber of Engineers in Investment and Design. At that event, not only was the presentation on high-efficiency heat recovery ventilation shown, but a discussion was also held around common challenges architects and designers face during the joint work they do when designing and executing energy efficient buildings.

The desire of the company is that these events become annual and that during public debates around energy efficiency the public pay attention not only to insulations, windows and construction products, but also to HVAC systems. These systems are one of the biggest consumption of energy for heating, cooling and ventilating buildings.

National Service Telephone:
0887 73 73 75