Heat Recovery Effectiveness Test Standards

Inhaltsverzeichnis

• Sensible effectiveness ηs = (Tsupply − Toutdoor) / (Textract − Toutdoor). Enthalpy (total) effectiveness ηt = (hsupply − houtdoor) / (hextract − houtdoor), using moist-air enthalpy. Latent effectiveness uses humidity ratio in place of enthalpy.
• Standard Scope EN 308 Test procedures for air-to-air and flue-gas heat recovery devices (sensible and latent). EN 13053 Rating and performance of air-handling units, including heat recovery sections and pressure drop. EN 13141-7 Performance testing of residential mechanical supply/exhaust ventilation units. AHRI 1060 / 1061 Energy recovery ventilators — the method ASHRAE 90.1 references for its 50% minimum.
• Test conditions differ: Ecodesign measures ηt at −10 °C, 0 °C, and +10 °C outdoor; ASHRAE uses design heating and cooling conditions. A wheel rated 75% by AHRI 1060 may read differently under EN 308 because of how leakage and frost are handled. Pressure drop is part of the story — a more effective core that needs a bigger fan can erase the saving, which is why Ecodesign SFP limits bind efficiency and fan power together.
• Use the measured ηt from the relevant standard when checking code floors. For non-rotating critical ventilation, compare a membrane core against a wheel on the same test basis, and fold the pressure drop into the AHU selection calculation.

“Effectiveness” is the number every code and rating system quotes, but the value only means something if the test method is stated. This article maps the main heat recovery effectiveness test standards and how they define the metric.

• Sensible effectiveness η_s = (T_supply − T_outdoor) / (T_extract − T_outdoor).
• Enthalpy (total) effectiveness η_{t%b 0%b 7} = (h_supply − h_outdoor) / (h_extract − h_outdoor), using moist-air enthalpy.
• Latent effectiveness uses humidity ratio in place of enthalpy.

Standard	Scope
EN 308	Test procedures for air-to-air and flue-gas heat recovery devices (sensible and latent).
EN 13053	Rating and performance of air-handling units, including heat recovery sections and pressure drop.
EN 13141-7	Performance testing of residential mechanical supply/exhaust ventilation units.
AHRI 1060 / 1061	Energy recovery ventilators — the method ASHRAE 90.1 references for its 50% minimum.

• Test conditions differ: Ecodesign measures η_{t%b 0%b 7} at −10 °C, 0 °C, and +10 °C outdoor; ASHRAE uses design heating and cooling conditions.
• A wheel rated 75% by AHRI 1060 may read differently under EN 308 because of how leakage and frost are handled.
• Pressure drop is part of the story — a more effective core that needs a bigger fan can erase the saving, which is why Ecodesign SFP limits bind efficiency and fan power together.

Use the measured η_{t%b 0%b 7} from the relevant standard when checking code floors. For non-rotating critical ventilation, compare a membrane core against a wheel on the same test basis, and fold the pressure drop into the AHU selection calculation.