Content added to your bookmarks in MyHoval

File added to your bookmarks in MyHoval

There has been an error while adding Content to your bookmarks in MyHoval

Heat recovery in residential ventilation

Ventilation units with a nominal air flow rate of less than 250 m3/h are residential ventilation units (RVUs) and are therefore not subject to the regulations for AHU systems, which have a nominal air flow rate greater than or equal to 1000 m3/h. In the range between 250 and 1000 m3/h, the manufacturer does not have to declare the unit’s intended use. 

Residential ventilation units take extract air out of the rooms being ventilated and replace it with fresh air. A heat recovery unit transfers heat – and sometimes also humidity – from the extract air to the supply air (tip 1: heat recovery).

Residential ventilation units have no reheater for the fresh air; therefore, the heat recovery
efficiency has to be high. As a result, it makes sense that rotary heat exchangers and counterflow plate heat exchangers with a temperature efficiency of more than 80% are used.

As the system runs all year round, very low outdoor temperatures also have to be tolerated.
The energy balance is then ensured by internal heat (from the heating system, kitchen, bathroom). During planning, leakage (tip 4: leakage) and condensate (tip 5: condensation in the extract air) must also be considered.

Sorption rotary heat exchangers transfer humidity throughout the year, whereas condensation rotary heat exchangers only do this when outdoor temperatures are low and if condensate forms. Membrane plate heat exchangers also transfer humidity (tip 7: humidity transfer).
Residential ventilation is mandatory in Europe due to regulations regarding building insulation and tightness. As there is no supply air heater, a highefficiency heat recovery unit is an essential part of the system. An economic efficiency calculation provides information on which system (plate heat exchanger, rotary heat exchanger) to choose.

Solutions from Hoval

Hoval supplies rotary heat exchangers (condensation and sorption rotary heat exchangers) for this application. As a pioneer in heat recovery, Hoval has decades of practical experience and the application expertise required. 

Ask for advice on heat exchangers for residential ventilation units

We’ll help answer any questions you have regarding the ideal heat exchanger for residential ventilation units. 

You’ll benefit from an all-inclusive package ranging from expert advice and reliably high product quality to delivery within short delivery times.