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Highest-UEF gas tank water heaters

Gas-fired storage tanks, ranked by filed UEF inside each draw pattern.

711 gas tank water heaters are on file. Ranked by filed UEF inside each draw pattern, the highest filed UEF at the high draw pattern is UEF 0.9, shared by 20 models. 17 models named in a CPSC recall are left out.


Editor's note

Gas tank UEFs sit close together at the medium draw pattern, so only the draw patterns where they spread far enough to order are ranked.


High draw pattern

a larger household, or one where showers and laundry overlap — 408 models, top 25 shown, highest UEF first.

  1. Tied at rank 1: A. O. SMITH GPCT-40L 1** 188 therms/yr UEF 0.9
  2. Tied at rank 1: A. O. SMITH GPCX-50L 1** 188 therms/yr UEF 0.9
  3. Tied at rank 1: AMERICAN GPCT-40L 1** 188 therms/yr UEF 0.9
  4. Tied at rank 1: AMERICAN GPCX-50L 1** 188 therms/yr UEF 0.9
  5. Tied at rank 1: Envirosense Enercare GPCT-40L 1** 188 therms/yr UEF 0.9
  6. Tied at rank 1: Envirosense Enercare GPCX-50L 1** 188 therms/yr UEF 0.9
  7. Tied at rank 1: Envirosense GPCT-40L 1** 188 therms/yr UEF 0.9
  8. Tied at rank 1: Envirosense GPCX-50L 1** 188 therms/yr UEF 0.9
  9. Tied at rank 1: Envirosense Reliance Home Comfort GPCT-40L 1** 188 therms/yr UEF 0.9
  10. Tied at rank 1: Envirosense Reliance Home Comfort GPCX-50L 1** 188 therms/yr UEF 0.9
  11. Tied at rank 1: FRIEDRICH PROP G40-50* RH HE EC3 188 therms/yr UEF 0.9
  12. Tied at rank 1: LOCHINVAR GPCT-40L 1** 188 therms/yr UEF 0.9
  13. Tied at rank 1: LOCHINVAR GPCX-50L 1** 188 therms/yr UEF 0.9
  14. Tied at rank 1: RELIANCE WATER HEATERS GPCT-40L 1** 188 therms/yr UEF 0.9
  15. Tied at rank 1: RELIANCE WATER HEATERS GPCX-50L 1** 188 therms/yr UEF 0.9
  16. Tied at rank 1: Rheem PROP G40-50* RH HE EC3 188 therms/yr UEF 0.9
  17. Tied at rank 1: Richmond PROP G40-50* RH HE EC3 188 therms/yr UEF 0.9
  18. Tied at rank 1: Ruud PROP G40-50* RH HE EC3 188 therms/yr UEF 0.9
  19. Tied at rank 1: STATE GPCT-40L 1** 188 therms/yr UEF 0.9
  20. Tied at rank 1: STATE GPCX-50L 1** 188 therms/yr UEF 0.9
  21. Tied at rank 21: FRIEDRICH PROP G50-50* RH HE EC3 192 therms/yr UEF 0.88
  22. Tied at rank 21: Rheem PROP G50-50* RH HE EC3 192 therms/yr UEF 0.88
  23. Tied at rank 21: Richmond PROP G50-50* RH HE EC3 192 therms/yr UEF 0.88
  24. Tied at rank 21: Ruud PROP G50-50* RH HE EC3 192 therms/yr UEF 0.88
  25. Tied at rank 25: ECOSENSE RHE40S 204 therms/yr UEF 0.83

3 more models in this draw pattern also file UEF 0.83; the list stops at 25, not at a difference.


Not ranked

Low draw pattern (9 models): the filed UEFs vary by only 2.6% — too close together to order meaningfully.

Medium draw pattern (277 models): the filed UEFs vary by only 5.5% — too close together to order meaningfully.


How this list is ranked

One filed figure decides the order, inside one draw pattern at a time — the only scope where it compares. Models that file the same figure share a rank, shown as =N. A draw pattern is ranked only when it holds at least eight models and their figures spread by at least 8%; models named in a CPSC recall are left out.

DOE CCD · 2026-09-19