/ Field knowledge · IMC 513
Name the airstream before you recover it.
IMC 513: you cannot recover energy from every airstream. Ask what exact exhaust you are recovering from before you model the unit.
Educational 2024 IMC 513. Confirm adopted edition and IECC if ERV is required for energy. This is not an ERV selection.
- Ducted HRVs listed/labeled to UL 1812. Nonducted HRVs to UL 1815. If energy code requires ERV, also comply with IECC.
- 513.2 prohibited: hazardous exhaust (509); dust/stock/refuse conveying explosive or flammable vapors, fumes, or dust; smoke control (512); commercial kitchen exhaust serving Type I hoods; clothes dryer exhaust (504). Exception: sensible-only recovery using coil-type heat exchangers is not limited by this prohibition.
- Access to the heat exchanger and other components for service, maintenance, repair, or replacement.
- Air is not considered recirculated if cross-leakage is limited to less than 10% of total design airflow. Document it.
ERV on a Type I hood
An ERV on a prohibited airstream is a 513.2 violation regardless of how well the unit is specified. Reverse supply/exhaust is invisible without a flow measurement at commissioning.
Source: DCT 513 · tool: ERV eligibility · Type I: 506–508 · dryers: 504.
What to send
The exact exhaust airstream feeding the ERV, listing cut sheet, and whether anyone already tied it to a hood or dryer.
If the ERV is recovering “whatever is on the roof”
Send the airstream. Masterbuild will say whether 513 even allows recovery — or this is a prohibited 509/512/Type I/504 connection.
Send Project Background+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com
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