Tips on choosing ventilation systems

niusha ztm

HRV vs ERV and the definition of each

Heat recovery ventilation (HRV), also known as mechanical ventilation heat recovery (MVHR), is an energy recovery ventilation system which works between two sources at different temperatures. Heat recovery is a method which is increasingly used to reduce the heating and cooling demands (and thus energy costs) of buildings. By recovering the residual heat in the exhaust gas, the fresh air introduced into the air conditioning system is pre-heated (pre-cooled), and the fresh air enthalpy is increased (reduced) before the fresh air enters the room or the air cooler of the air conditioning unit performs heat and moisture treatment.A typical heat recovery system in buildings consists of a core unit, channels for fresh air and exhaust air, and blower fans. Building exhaust air is used as either a heat source or heat sink depending on the climate conditions, time of year and requirements of the building. Heat recovery systems typically recover about 60–95% of the heat in exhaust air and have significantly improved the energy efficiency of buildings .


To choose between HRV and ERV ventilation systems, we need to know the difference between heat recovery ventilation and energy recovery ventilator, the exact introduction and application of each. Stay with us.



Energy recovery ventilation (ERV) is the energy recovery process in residential and commercial HVAC systems that exchanges the energy contained in normally exhausted air of a building or conditioned space, using it to treat (precondition) the incoming outdoor ventilation air. The specific equipment involved may be called an Energy Recovery Ventilator, also abbreviated ERV.

The main difference between HRV and ERV systems is in their center unit. Whereas an HRV’s heat recovery core’s separating wall are moisture-sealed, those in an ERV are different: they consist of a desiccant substance (which absorbs some of the moisture).



The ERV conveys moisture from the more humid airstream to the least moist stream. In winter, when moisture rates are typically higher in the home than outside, the ERV dries exhausted air and damps entering the air. It can be said that during the cold months, an ERV keeps more moisture in the home than an HRV. More information at this link







niusha ztm
Zupyak is a free content platform for publishing and discovering stories, software and startups.