ENVO WH-AZ53-180-LPO vs Fogatti FDG-PM180S: which uses less energy?
At the high draw pattern the ENVO WH-AZ53-180-LPO uses 202 therms a year and the Fogatti FDG-PM180S 206 — 5 therms (2%) less, about 49 therms over ten years. Both are filed as a gas tankless unit, 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 tankless unit at the high draw pattern.
| Figure | ENVO WH-AZ53-180-LPO | Fogatti FDG-PM180S |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.84 (better) | 0.82 |
| Energy use per year (therms) | 202 (better) | 206 |
| Max flow (GPM) | 4.5 | 4.5 |
| Installed cost range | $1,839–$2,798 | $1,745–$2,687 |
| ENERGY STAR certified | not matched | not matched |
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 below.
- The actual warranty term is printed in each model’s documentation, not in any registry.
Which should you pick?
- Pick the ENVO WH-AZ53-180-LPO if running cost matters most: it uses 5 therms less a year on the same test.
- Pick the Fogatti FDG-PM180S if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the ENVO WH-AZ53-180-LPO.
- Neither if you need more than 4.5 GPM at the same time — neither unit lists more. Check how to size a tankless unit by GPM.
Each model on its own
-
ENVO WH-AZ53-180-LPO
Its filed figures, class position and running cost on your ZIP.
-
Fogatti FDG-PM180S
Its filed figures, class position and running cost on your ZIP.