DoesTheMath

RELIANCE WATER HEATERS GUC-30 4** vs U.S. CRAFTMASTER GCB-30R 4**: which uses less energy?

At the medium draw pattern the U.S. CRAFTMASTER GCB-30R 4** uses 185 therms a year and the RELIANCE WATER HEATERS GUC-30 4** 188 — 3 therms (2%) less, about 31 therms over ten years. Both are filed as a gas tank, so the comparison holds. Enter your ZIP below to price the difference.

Side by side

Compared within one class only: models filed as a gas tank at the medium draw pattern.

Filed and computed figures
RELIANCE WATER HEATERS GUC-30 4** U.S. CRAFTMASTER GCB-30R 4**
UEF (Uniform Energy Factor) 0.59 0.6 (better)
Energy use per year (therms) 188 185 (better)
First hour rating (gal) 62 62
Rated storage volume (gal) 29 29
Installed cost range not published not published
ENERGY STAR certified not matched not matched
DOE CCD · 2026-09-19

What it costs to run

RELIANCE WATER HEATERS GUC-30 4**: 188 therms a year U.S. CRAFTMASTER GCB-30R 4**: 185 therms a year

RELIANCE WATER HEATERS GUC-30 4** — 188 therms a year U.S. CRAFTMASTER GCB-30R 4** — 185 therms a year

U.S. CRAFTMASTER GCB-30R 4** is 3 therms a year lower than RELIANCE WATER HEATERS GUC-30 4**.

DOE CCD · 2026-09-19

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Reliability

Not published: Reliability, failure rates and each model’s actual warranty term.

The registries these figures come from certify energy performance under a federal test; none of them records how long a unit lasts or how often it fails, so this page does not rank the two on reliability.

What is here instead:

  • The filed efficiency, capacity and tank size of both models, side by side below.
  • The actual warranty term is printed in each model’s documentation, not in any registry.

Which should you pick?

  • Pick the U.S. CRAFTMASTER GCB-30R 4** if running cost matters most: it uses 3 therms less a year on the same test.
  • Pick the RELIANCE WATER HEATERS GUC-30 4** if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the U.S. CRAFTMASTER GCB-30R 4**.
  • Neither if your household's busiest hour needs more than 62 gallons of hot water — neither lists more. Check whether a 30-gallon heater is enough.

Each model on its own

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