Uniformat D3050

Water-source heat pump

A water-source heat pump lasts about 19 years, the median of 3 published sources, which state 15–21 years.

Also listed as WSHP, geothermal heat pump

• Confidence C
• Version 0.4.0 (permanent link)
• Reviewed 2026-10-23

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

• 19 years · Energy Conservation Program: Energy Conservation Standards for Water-Source Heat Pumps (request for information), 85 FR 27929, May 12, 2020, p11 · H “equipment lifetime on a retirement function in the form of a Weibull probability distribution, with a mean of 19 years” — U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (planning life)
  Printed page 27939. Direct match: commercial water-source heat pumps (water-to-air, under 135,000 Btu/h). Value from the July 2015 final rule, restated in this RFI.
• 21 years · Updated Buildings Sector Appliance and Equipment Costs and Efficiencies (March 2023), Appendix A: EIA - Technology Forecast Updates - Residential and Commercial Building Technologies - Reference Case (Guidehouse and Leidos, March 3, 2023), p145 · Commercial Ground-Source Heat Pumps “Average Life (y) 21 (all years, typical and high efficiency)” — U.S. Energy Information Administration; Appendix A prepared by Guidehouse and Leidos (planning life)
  Printed page 141 (Appendix A). Commercial 4-ton (48 kBtu/h) closed-loop ground-source water-to-air heat pump, the same unit type as a water-source heat pump (DOE regulates both as water-source heat pumps). Data-source sheet (PDF p.241, A-61) gives the life source as 'Guidehouse / Water-Source Unitary Heat Pumps EERE 2015 Final Rule'. That rule (80 FR 42614) used a 19-year mean, so the 21 years is the contractor's figure.
• 15 years · Purchasing Energy-Efficient Geothermal Heat Pumps (web page, modified 2026-09-15) · Tables 2 and 3 assumptions “Lifetime Energy Cost: The sum of the discounted values of annual energy cost with an average residential geothermal heat pump life of 15 years.” — U.S. Department of Energy, Federal Energy Management Program (planning life)
  Residential geothermal (ground-source) heat pumps, single-phase, open loop, closed loop and direct geoexchange (ENERGY STAR scope). Same water-to-air unit type as a water-source heat pump, but residential; commercial use is not stated. All three tables (Southeast, Southwest, Northern) use 15 years.

How sources are chosen and recorded: sourcing policy.

Preventive maintenance

11 tasks in 1 work order.

1. 1
2. 2
3. 3
4. 4
5. 5
6. 6
7. 7
8. 8
9. 9
10. 10
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.
• Written for GSA contracted O&M in US federal buildings; job plans are generic and defer to manufacturer instructions, and the fire extinguisher plans only point to NFPA 10.

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

Cite this

Citation

unfinished.one (2026). Water-source heat pump, v0.4.0. https://unfinished.one/c/water-source-heat-pump/v/0.4.0

BibTeX

@misc{unfinished_water_source_heat_pump_0_4_0,
  title = {Water-source heat pump},
  author = {{unfinished.one}},
  year = {2026},
  version = {0.4.0},
  url = {https://unfinished.one/c/water-source-heat-pump/v/0.4.0},
  note = {CC BY 4.0}
}

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