{"id":"supply-return-fan","version":"0.1.0","classification":{"uniformat":"D3040"},"names":["Supply or return fan"],"aliases":["SF","RF","inline fan","supply fan","return fan"],"service_life":{"median_years":15,"range_years":[15,15],"range_basis":"source_spread"},"pm_tasks":[{"task":"Shut down or re-sequence equipment that is not needed","frequency":"P1D","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Do an overall visual inspection: all equipment operating and safety systems in place","frequency":"P1D","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Check belt tension and alignment","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Inspect pulleys; clean and lubricate as needed","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Check dampers close fully; outside air dampers airtight when closed","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Check actuator and linkage operation; clean, lubricate, adjust","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Check fan blades rotate correctly; clean when needed","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Check filters for gaps; replace when dirty","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Inspect for moisture or growth on surfaces and ducts; check odours and complaints","frequency":"P1M","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Check electrical connections are tight","frequency":"P1Y","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Inspect ductwork; refasten loose connections and repair leaks","frequency":"P1Y","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Coils: confirm filters have been kept clean","frequency":"P1Y","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"},{"task":"Inspect and repair or replace damaged duct insulation","frequency":"P1Y","reference":"Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency, Release 3.0","url":"https://www.energy.gov/sites/default/files/2020/04/f74/omguide_complete_w-eo-disclaimer.pdf","page":218,"checklist":"9.8.11 Fans Checklist"}],"basis":[{"type":"public_document","life_type":"planning","title":"Energy Conservation Program: Energy Conservation Standards for Fans and Blowers (notice of proposed rulemaking), 89 FR 3714, January 19, 2024","by":"U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy","url":"https://www.govinfo.gov/content/pkg/FR-2024-01-19/pdf/2023-28976.pdf","page":75,"code":"IV.F.6","label":"Equipment Lifetime: GFBs, \"15 years in the commercial sector based on the expected lifetimes of HVAC equipment\"","years":15,"note":"Printed page 3788. Commercial-sector lifetime for general fans and blowers (all fan types). Proposed rule; the 15 years is borrowed from HVAC equipment lifetimes, not fan data."}],"confidence":{"grade":"C","sample_size":null},"open_questions":["Every source here is a published planning, design or accounting life. None is observed replacement data."],"contributors":["unfinished.one editors"],"last_reviewed":"2026-10-21","canonical_url":"https://unfinished.one/c/supply-return-fan","versioned_url":"https://unfinished.one/c/supply-return-fan/v/0.1.0","licence":"CC-BY-4.0","citation":"unfinished.one (2026). Supply or return fan, v0.1.0. https://unfinished.one/c/supply-return-fan/v/0.1.0"}