[B]Plate Heat Exchanger (Cross-flow Heat Exchanger, Counter-flow Heat Exchanger)[/B] In all plate heat exchangers, the air is guided through a package of parallel, thin plates (alternating layers of supply air and exhaust air). The energy is transferred from the warm air to the cold air through the heat-conducting plate.
+ No moving parts, low maintenance
+ Simple structural design
+ Consistent separation of supply air and exhaust air, no mixing
- Precautions against frost risk must be taken (e.g., electric supply air preheating or ground heat exchanger), otherwise condensate formed could lead to icing
Rotary Heat Exchanger: In this technology, a rotor consisting of numerous channels parallel to the axis of rotation turns (appearance similar to corrugated cardboard, but made of corrosion-resistant thin metal or foil). Each channel is as long as the rotor is thick. One half of the rotor (e.g., top) is flowed through by the exhaust air, the other half (e.g., bottom) is flowed through in the opposite direction by the supply air. The part of the rotor at the top is thus "charged" with the heat of the exhaust air and then rotates into the cold supply air. Accordingly, each individual channel is heated for half a rotation and can then release this heat again for half a rotation.
+ Moisture condenses on the cold rotor and is reabsorbed by the supply air, thus fewer problems with too dry air (re-humidification of the air)
+ No precautions necessary for frost protection
+ Also suitable for large air volumes
+ Drive motor and seals required, thus possibly somewhat more failure-prone than plate heat exchangers
- Additional energy required for drive motor
- Theoretical contamination of the rotor and thus the supply air possible, furthermore slight air mixing with odor transfer possible. (up to 30%!!!!)
So I would not want to have a rotary exchanger... and what can Hoval do better now?
