Uniformat D3020

Gas furnace

A gas furnace lasts about 20 years, the median of 6 published sources, which state 15–25 years.

Also listed as Furnace, gas-fired, furnace, forced air furnace

• Confidence C
• Version 0.5.0 (permanent link)
• Reviewed 2026-10-22

Service life

Years in service. The band runs from the shortest to the longest life the sources state, so it shows how much they disagree, not how long 80% of units last. The line is the median of the stated lives.

Work out when yours is due for replacement

Basis

• 20 years · CNA e-Tool Estimated Useful Life Table, p12 · HUD CNA 3.4.3.1.4 “Gas furnace/air handler” — U.S. Department of Housing and Urban Development (planning life)
  Same life for family and elderly properties. US multifamily housing. The municipal rows say furnace without naming the fuel.
• 15 years · The Blue Mountains: POL.COR.19.04 Tangible Capital Assets Policy, p11 (accounting life)
  Capital asset policy (amortization period). Approved on text check: the label and value were found on the cited page.
• 15 years · Grey Highlands: By-law No. 2026-052, Tangible Capital Asset Policy A09-F-03, p11 (accounting life)
  Capital asset policy (amortization period). Approved on text check: the label and value were found on the cited page.
• 15–25 years · Meaford: By-law 2020-83, Tangible Capital Asset Policy, Appendix A Estimated Useful Lives, p17 (accounting life)
  Capital asset policy (amortization period). Approved on text check: the label and value were found on the cited page.
• 23 years · Energy Conservation Program for Certain Industrial Equipment: Energy Conservation Standards for Small, Large, and Very Large Air-Cooled Commercial Package Air Conditioning and Heating Equipment and Commercial Warm Air Furnaces (direct final rule), 81 FR 2420, January 15, 2016, p4 · “"the average lifetime of the equipment, which is estimated to be 23 years for both gas-fired and oil-fired CWAFs"” — U.S. Department of Energy (planning life)
  Printed page 2423. class: commercial warm air furnaces >=225,000 Btu/h input, gas-fired and oil-fired. Commercial, mostly weatherized/rooftop-mounted; residential furnaces are covered separately (consumer furnace rule). Lifetime derived from the CUAC lifetime (section IV.F.6.b, p.60, printed 2479).
• 21.5 years · Energy Conservation Program: Energy Conservation Standards for Consumer Furnaces (final rule), 88 FR 87502, December 18, 2023, p70 · IV.F.6 “"DOE estimates the average product lifetime to be 21.5 years for NWGFs and MHGFs"” — U.S. Department of Energy (planning life)
  Printed page 87571. residential: non-weatherized gas furnaces and mobile home gas furnaces; national average. Regional averages 22.5 years (North) and 20.2 years (rest of country) in the same paragraph. Also p.2 (printed 87503).

How sources are chosen and recorded: sourcing policy.

Preventive maintenance

10 tasks in 3 work orders. Intervals that fall due together are one visit: the every 2 years visit also covers the every 2 months and annual tasks.

1. 1
2. 2Every 2 months
3. 3
4. 4Every 2 months
5. 5
6. 6Every 2 months
7. 7
8. 8Every 2 months
9. 9
10. 10Every 2 months
11. 11
12. 12Annual

Months from the schedule start. Download the tasks as CSV for a CMMS, or ask the MCP tool get_pm_schedule for dated visits.

Frequencies are ISO 8601 durations in the data (P3M = every 3 months).

Open questions

• Every source here is a published planning, design or accounting life. None is observed replacement data.
• Furnace tasks come from Army TM 5-642 (1990); equipment and practice may have changed since.

Know the answer? Send it with a source to [email protected].

Cite this

Citation

unfinished.one (2026). Furnace, gas-fired, v0.5.0. https://unfinished.one/c/furnace-gas/v/0.5.0

BibTeX

@misc{unfinished_furnace_gas_0_5_0,
  title = {Furnace, gas-fired},
  author = {{unfinished.one}},
  year = {2026},
  version = {0.5.0},
  url = {https://unfinished.one/c/furnace-gas/v/0.5.0},
  note = {CC BY 4.0}
}

Licence CC BY 4.0 · How to cite · JSON · Versions: 0.5.0, 0.4.0, 0.3.0, 0.2.0, 0.1.0