Energy recovery ventilation
The difference between HRV heat recovery ventilation and ERV energy recovery ventilation is the humidity. In a plate heat exchanger, the air flows are separated by metal plates. Humidity can not be exchanged.
Rotating heat exchanger with many small flues
The rotating heat exchanger is made by a material able to absorb humidity. In the rotating part are many holes for the air. During one full rotation, a flue is half time on the side where the cold outside air is warmed up by the rotating heat exchanger. The warmed up air goes into the living space.
The second half is for the air leaving the living space to go as waste air outside. The warm air from the living space warms up the flue walls.
The same pipes are used one time to warm the incoming air, and later to cool down the outgoing air. This makes the main problem at the rotating type of ERVs. The smells in the outgoing air can also come into the material of the rotating unit and be taken by the incoming air.
Plate heat exchanger with humidity permeably material
This new method was introduced 2006 by Paul, a special company for airing systems for passive houses. A crosscurrent countercurrent air to air heat exchanger built with a humidity permeably material.
Passive Houses
The term Passive house (Passivhaus in German) refers to the rigorous, voluntary, Passivhaus standard for energy use in buildings. It results in ultra-low energy buildings that require little energy for space heating. A similar standard, MINERGIE, is used in Switzerland .
One of the original Passive Houses at Darmstadt, Germany
The first Passivhaus buildings were built in Darmstadt, Germany, in 1990, and occupied the following year. In September 1996 the Passivhaus-Institut was founded in Darmstadt to promote and control the standard. Since then more than 6,000 Passivhaus buildings have been constructed in Europe, most of them in Germany and Austria, with others in various countries world-wide.
Despite the name, the standard is not confined only to houses. Several office buildings, schools, kindergartens and a supermarket have also been constructed to the standard. Although it is mostly applied to new buildings, it has also been used for refurbishments.
Source:Wikipedia, the free encyclopedia