目次
- Regime Trigger Minimum recovery ASHRAE 90.1-2022 (US) ≥ 5,000 CFM and ≥ 70% OA 50% enthalpy (AHRI 1060) IECC / most US state codes adopt 90.1 by reference same 50% floor California Title 24 (US) high OA fractions, large systems 50%+ sensible, climate-tuned EU Ecodesign 1253/2014 units ≥ 30 W fan power 73% (ηt), 68% run-around EU EPBD 2024/1275 ZEB by 2030 (policy driver) recovery expected, not a fixed %
- The US rules trigger on system size and outdoor-air fraction; the EU rule triggers on equipment placed on the market and sets an absolute 73% thermal efficiency. California Title 24 tightens the sensible floor in cold climates and ties recovery to economizer controls. The EPBD does not state a percentage but makes recovery the practical path to a fossil-free, near-zero-energy building — see EPBD zero-emission buildings.
- Specifying a core at 70–75% enthalpy effectiveness clears the US 50% floor, the EU 73% Ecodesign floor, and most Title 24 climate tiers at once. Use the test standards to confirm the number is measured on the right basis, and the ASHRAE 90.1 and Ecodesign articles for the exact exceptions. The result is a single specification that satisfies auditors on both sides of the Atlantic.
あcross jurisdictions, building codes increasingly mandate energy recovery once a system serves enough outdoor air. This overview compares the main regimes so a designer can specify one core that clears them all.
| Regime | Trigger | Minimum recovery |
|---|---|---|
| ASHRAE 90.1-2022 (US) | ≥ 5,000 CFM and ≥ 70% OA | 50% enthalpy (AHRI 1060) |
| IECC / most US state codes | adopt 90.1 by reference | same 50% floor |
| California Title 24 (US) | high OA fractions, large systems | 50%+ sensible, climate-tuned |
| EU Ecodesign 1253/2014 | units ≥ 30 W fan power | 73% (η% e8t1TP 3T811 TP3Tb2), 68% run-around |
| EU EPBD 2024/1275 | ZEB by 2030 (policy driver) | recovery expected, not a fixed % |
- The US rules trigger on system size and outdoor-air fraction; the EU rule triggers on equipment placed on the market and sets an absolute 73% thermal efficiency.
- California Title 24 tightens the sensible floor in cold climates and ties recovery to economizer controls.
- The EPBD does not state a percentage but makes recovery the practical path to a fossil-free, near-zero-energy building — see EPBD zero-emission buildings.
Specifying a core at 70–75% enthalpy effectiveness clears the US 50% floor, the EU 73% Ecodesign floor, and most Title 24 climate tiers at once. Use the test standards to confirm the number is measured on the right basis, and the ASHRAE 90.1 and Ecodesign articles for the exact exceptions. The result is a single specification that satisfies auditors on both sides of the Atlantic.