Differences

This shows you the differences between two versions of the page.

--- planning:building_services:ventilation:basics:types_of_ventilation [2015/09/01 10:12] – [The convenient solution: supply and exhaust air systems with heat recovery] sensible heat wfeist
+++ planning:building_services:ventilation:basics:types_of_ventilation [2015/09/01 10:13] – [The convenient solution: supply and exhaust air systems with heat recovery] wfeist
@@ Line 130: / Line 130: @@
 \\
 The highly efficient ventilation units developed for the Passive House have also proved to be effective  in **modernisations of existing buildings**. Here they contribute to the improvement of the air quality, and ensure that mould growth does not occur at weak points in external building components, as well as helping to save energy.
-An additional possibility for improving the efficiency of ventilation systems is offered by the **subsoil heat exchanger**: on average, the ground is warmer in winter than the surrounding air, and colder in summer.  Fresh air can therefore be pre-heated or pre-cooled using the earth.  This can take place directly through air ducts (air-to-soil heat exchanger) or indirectly by means of a hydraulic system (brine-carrying subsoil heat exchanger).\\
 In hot climates, air-to-air counterflow heat exchangers can also help to recover "cool temperature" from the exhaust air and to reduce the temperature of the supply air, if the fresh air is uncomfortably hot. But this requires low energy fans in order to reduce heat loads caused by the ventilators. Humidity recovery, which is possible with special types of heat exchangers, is another highly efficient option in extreme cold and/or extreme hot and humid climates.\\