The Revolution in Ventilation

TopAir ventilation cuts energy costs

TopAir is a rooftop installed energy-efficient and  on-demand controlled air ventilation solution. Already equipped with a machine-operated exhaust ventilation be installed on all apartment houses. TopAir differs from other top fans insofar that it uses modern sensor technology instead of old-fashioned clock control. TopAir reacts automatically to changes of air quality (e.g. smells or room occupancy) by increasing or decreasing the air volume flow. The automatic flow control prevents unnecessary waste of heating energy. Thus, there are no more unnecessary losses of heating energy. During its lifecycle TopAir may save money in tenth of thousands of Euro.


TopAir also improves the indoor air quality. Drafts are minimized or disappear completely because there is no needless surplus exhaust of indoor air. Additionally, the indoor humidity is optimized according to seasonal change. Investment in this new technology and its installation increases the value of the apartments and even the propertys lifecycle. TopAir is very quiet, and most of the day its existence is barely noticeable.


The refurbishment of the ventilation cuts costs, adds living comfort and presents an ecologic solution.


Cost reduction for property owners, better living quality for the residents

Provided the building already possess a machine-operated ventilation, the TopAir system can be installed at any time onto the roof of the building. TopAir is a worthwhile investment for rental housing companies, student housings as well as for private property owners.

Its installation allows a remarkable reduction of energy waste and thus less costs. Since heating causes a lot of pollution energy-efficiency means also ecological responsible.

Apartment building residents

TopAir is designed to improve the air quality in a real estates, hence in turn improving the residents living comfort. Since the TopAir is much quieter than common exhaust systems, the whole ventilation system quiets down.


On-demand controlled ventilation prevents needless draft. It reduces compounds impairing the indoor air quality, such as e.g. cooking odours.

Property manager / Property owner

TopAir provides an inexpensive way to modernize the ventilation at once. Its installation comes without prolonged downtime or disturbing measures regarding the residents.


TopAir cuts the energy expenses of the property rendering it more profitable. It also prolongs the properties life cycle. Moreover, residents are more satisfied with their accommodation.


Due to TopAirs remote controllability it is carefree hence reducing the property managers workload. TopAir also provides intelligible reports to verify the savings. TopAir is also in line with today’s values and concerns regarding the environment.


HVAC- Professional

TopAir offers the HVAC-Professional an easy solution to modernize centralized exhaust ventilation systems. The remote controllability of the ventilation system enables service personnel to easily monitor, maintain and identify errors. Moreover, TopAir will automatically report any abnormal values (e.g via SMS). Hence it leads to much shorter respond times in case of failures. Due to its plug and play features TopAirs installation is fast and easy. The product will be tailored to the demands of the property in question.


We offer a reliable and flexible partnership as well as adaptive products for a changing market. We design innovative premium-quality ventilation solutions employing cutting edge HVAC technology.

Clicking the button leads you to the TopAir EC energy consumption charts.

Clicking onto the button will lead you to our frequently asked questions (and answers) section concerning TopAir.



TopAir already cuts costs in the following cities:

  • Rovaniemi

  • Oulu

  • Kuopio

  • Äänekoski

  • Jyväskylä

  • Mikkeli

  • Lahti

  • Lappeenranta

  • Tampere

  • Turku

  • Hämeenlinna

  • Vantaa

  • Salo

  • Espoo

  • Helsinki

  • Porvoo

  • Kotka



Ventilation means the intentional replacement of indoor air by introduction of outdoor air. The stale indoor air is hereby led through the exhaust duct outside of the building. This creates a vacuum in the interior which is sought to be filled with fresh supply air. Fresh outdoor air is introduced into the apartment via air supply valves, fresh air valves or windows. Otherwise fresh air enters the building through leaks. As a rule, at least 50% of a flats air should be changed per hour.

Ventilation can be accomplished in three different ways, these are natural and adventitious ventilation, mixed mode (hybrid) and mechanical ventilation.

Natural and adventitious ventilation

Especially in buildings completed before the 1960s the air exchange is performed by either adventitious or natural ventilation. The air exchange is accomplished due to temperature and pressure gradients as well as wind. Due to these gradients air flows in and out of the dwellings by means of valves and ducts (natural ventilation) or leakages (adventitious ventilation). Since this method is weather dependent, it tends to lead too far too much air flow in winter while in summer it might not work at all.

Hybrid ventilation

Between the 1960s and 2000s the hybrid system was the most popular ventilation type in Finland. Hybrid ventilation system uses ducts to transport the exhaust air outside. The end of the duct is hereby connected to a ventilator, which is typically installed on the roof. Fresh air is introduced either by mechanical means (e.g. fresh air valves) or by e.g. leaks in the building. The exhaust fan (on the roof) operates at two speeds and is controlled by an interval timer. According to its setting the interval timer regulates the fans speed either to full or halve speed. It is therefore important to estimate in advance when which speed is adequate.

Mechanical ventilation

In mechanical ventilation system a machine (e.g. a fan) handles the air flows of the supply air as well as of the exhaust air. Most air handling units also have means of heat recovery, thus recovering as much heat energy from the exhaust air as possible. If the recovery system does not provide enough energy to heat the supply air to the desired level, a post-heating radiator is used to raise the temperature of the supply air. This in turn will minimize draft sensations.


Ventilation is the one factor most important to indoor air quality. Insufficient ventilation leads to bad air quality and a raise in humidity. This may cause dizziness, tiredness, unwellness and poor concentration. Too much ventilation on the other hand can cause draft and may, especially in Winter, lead to so called dry air. However, most of these problems can be solved by refurbishing the ventilation system and air quality measurements.

Ventilation is also one of the properties biggest energy waster. Exhaust ventilation is responsible for about 35% of the overall heat consumption of a building. Thus, energy consumption can be reduced by, among other things, intelligent on-demand ventilation.


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Founded in 1977 ENTOS Energiatekniikan Optimisäätö Oy is a Mikkeli based HVAC company. We operate in the whole eastern region of Finland, offering all HVAC concerning services, such as equipment sales, installation, maintenance and planning. In cooperation with our partners TopAir sales and distribution is available all over Finland.


Aki Pohjalainen

Managing Director

Sami Savolainen

Chief Operating Officer

Toni Niskala

Production Manager

Postal address:

Jääkäritie 9

50150 Mikkeli


010 321 7530

Contact us and request a quotation