A. O. Smith GPCT-40L 1** vs John Wood GPVT-40 2**: which uses less energy?
An asterisk in a model number stands for any character: one filing covers several variants.
At the high draw pattern the A. O. Smith GPCT-40L 1** uses 188 therms a year and the John Wood GPVT-40 2** 242 — 54 therms (22%) less, about 537 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 high draw pattern.
| Figure | A. O. Smith GPCT-40L 1** | John Wood GPVT-40 2** |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.9 (better) | 0.7 |
| Energy use per year (therms) | 188 (better) | 242 |
| First hour rating (gal) | 86 | 87 |
| Rated storage volume (gal) | 38 | 38 |
| Installed cost range NLR REMDB | not published | $1,993–$3,665 |
| ENERGY STAR certified ENERGY STAR | yes | not matched |
| On the market since ENERGY STAR | 2021-10-01 | not filed |
| CPSC recall naming it CPSC | none on file | none on file |
DOE CCD · 2026-09-19 NLR REMDB · 2026-04-01 ENERGY STAR · 2026-09-19 CPSC · 2026-09-24
What it costs to run
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 above.
- No CPSC recall on file names either model (list checked 2026-09-24).
- The actual warranty term is printed in each model’s documentation, not in any registry.
Which should you pick?
- Pick the A. O. Smith GPCT-40L 1** if running cost matters most: it uses 54 therms less a year on the same test.
- Pick the John Wood GPVT-40 2** if you need more hot water in your busiest hour: it lists a first hour rating of 87 gallons against 86.
- Neither if your household's busiest hour needs more than 87 gallons of hot water — neither lists more. Check whether a 40-gallon heater is enough.
Each model on its own
- A. O. Smith GPCT-40L 1** 188 therms a year
- John Wood GPVT-40 2** 242 therms a year