Indoor humidity and living comfort
Does an enthalpy heat exchanger increase humidity in a house?
Yes, an enthalpy heat exchanger can transfer part of the moisture from exhaust air back into the supply air, helping to increase indoor humidity. This is not just a theoretical feature – it has been confirmed in real-world operation.
In an independent test carried out by an experienced user in their home with an AEREX ventilation unit, the long-term issue was very dry indoor air, despite attempts to naturally increase humidity, for example by using a large number of plants.
After installing the RECUTECH METALPIC enthalpy heat exchanger, there was a measurable increase in indoor humidity and an overall improvement in living comfort.
Under typical conditions, indoor humidity increases by approximately 10–15% during the heating season. In ideal conditions, the increase can reach up to 25–30%, depending on indoor humidity levels, airflow settings, and building characteristics.
Real measurement of indoor humidity with an enthalpy heat exchanger
It is important to understand that an enthalpy heat exchanger does not generate moisture, it only transfers it from the exhaust air back into the supply air. Therefore, the effect is not immediate but builds up gradually over several days to weeks.
This principle is based on physical laws and long-term real-world experience. That is why enthalpy heat exchangers are an effective solution for homes where ventilation systems cause excessive drying of indoor air.
This is why an enthalpy heat exchanger is one of the most effective solutions for dry indoor air in homes with ventilation systems.
An enthalpic heat exchanger will always help improve indoor humidity, as it transfers part of the moisture from exhaust air back into the fresh supply air. It cannot be guaranteed that ideal levels (typically 40–60%) will be achieved, since the final humidity also depends on other factors – such as household habits, number of occupants, natural moisture sources, and outdoor climate conditions.
However, we can guarantee that humidity will improve, because it is physically impossible for the return of moisture not to contribute to higher values.
An enthalpic heat exchanger does not generate humidity – it maximizes the transfer of humidity from exhaust air into fresh supply air. If you previously used a standard exchanger, not only the air but also the building structure (walls, ceilings, floors) and porous materials became dry. This means it may take some time for humidity levels to recover, so patience is necessary.
Every enthalpic exchanger we supply is fully functional and improvement is guaranteed. We recommend keeping natural humidity sources (plants, cooking, drying clothes). If you use humidifiers, continue using them until the humidity rises to a comfortable level with the enthalpic exchanger, after which they can be reduced.
Yes. Unlike a standard exchanger, an enthalpic heat exchanger transfers part of the humidity back into the fresh air. This process is gradual, but you can speed it up by adding humidity – either naturally (plants, drying clothes, washing floors) or with humidifiers. Once the humidity has returned to a stable, optimal level, additional humidification can be reduced.
No, an enthalpic heat exchanger does not generate humidity by itself. It only transfers part of the moisture from the exhaust air back into the fresh supply air. If humidity in your home is too high, the cause lies elsewhere (e.g., insufficient ventilation, drying clothes indoors without venting, or residual construction moisture). The enthalpic exchanger helps balance humidity and prevents extreme fluctuations.