What does ‘enthalpy heat recovery’ mean?

An enthalpy heat exchanger recovers both the sensible thermal energy (the heat) and the latent energy (the humidity) from the air flow. It has the advantage of offering better overall energy efficiency without over-drying the incoming air.

In controlled mechanical ventilation systems that use an enthalpy heat recovery system, energy efficiency affects both the temperature and humidity values of the extracted air flow. Helty system enthalpy heat exchangers are made with a polyethylene structure and a breathable fibrous membrane with antibacterial properties. The temperature is transferred from the warmer to the cooler air flow, and the humidity is also transferred (in the form of water vapour) from the flow with the higher vapour pressure to the lower pressure flow. The advantage of this technology is that the incoming air is not excessively dry and the balance of the home’s internal humidity is maintained.