How we experience the indoor climate are affected by different factors

Transpiration and breathing leads to heat and moisture delivery. How much is delivered depends on what activity is performed.

The air that is released in the free. After the exhaust air has passed the unit.

Air Circulation
Air that circulates inside a room or recovers air from the same room.

DOT (dimension outside temperature)
The calculated outside temperature for which the room air temperature drops a certain number of degrees (3 ° C) at an extreme outdoor temperature that occurs no more than once in x number of years. DOT varies depending on the climate of the city and how heavy the building is.

The air that is removed from a room. Usually kitchen, utility room, toilet, bath / shower room and storage room.

Uncontrolled ventilation due to the fact that outside air enters through immersion in the building.

Temperature differences between different surfaces cause heat transfer between the surfaces via radiation.

Thermal efficiency
How effective the heat exchanger is (stated in%). The efficiency depends on the airflow and the design outdoor temperature.

Heat transfer from body surface to ambient air. The amount of heat transfer depends on the temperature difference between the body surface and the air
as well as the movement of the air around the body.

Heat is transmitted via surface contact. For example, if the floor is cold, thermal comfort can be perceived as poor.

The sound level is measured in decibel (dB). The housing standards are 35 dB (A). The reverberation time, ie how fast the sound decreases depends on the furniture.
Rugs, curtains and furniture dampen the noise level.

Air Quality
Measured often with carbon dioxide concentration as an indicator. For housing, the limit value is 1000 ppm. The measured concentration is the sum of the concentration of the outdoor air and indoor air. The outdoor air concentration varies depending on where you live and the indoor air concentration on the number of persons, age, body weight and activity.

Turnover Air
How fast the air is exchanged in a room. The requirement says ½ turnover per hour. Ex. a room of 100 m² and room height 2.4 m (240 m³) shall have an airflow of 120 m³ / h (equivalent to approximately 33 l / s).

SFP (specific fan power)
The total power output of the ventilation system fans divided by the maximum flow of supply air or exhaust air. In order to have an energy-efficient ventilation system, the pressure drop in the duct system should be less than 1.2 Pa / m.

Thermal climate
The airspeed in the accommodation zone should contain more than 0.15 m / s and the temperature 22 ± 2 ºC. The experience of the indoor climate is very individual. Concentration and performance vary with temperature.

The air that is added to the system or room after treatment. Usually in the bedroom, living room, living room etc.

Depending on the air velocity and the area of ​​the channel (indicated in Pa). The pressure increases with increased velocity in air ducts.

Channel dimension Ø125 mm with air flow 30 l / s = total pressure drop of 0.7 Pa / m.

Outdoor air
Untreated air supplied to a ventilation system.

The part of the room used. The standard says 0.6m from the wall and 1.8m above the floor. In this area the requirements apply to temperatures and air velocities.

Over Air
Air that is transferred from one room to another. The air should be moved from a room with higher air quality to one with lower. For example, from the family room to the kitchen.