Choosing a commercial electric water heater for a business or industrial space usually comes down to three questions: how much hot water you need, what electrical supply you have, and how much you are prepared to pay. The four listings below span 50 to 120 gallons and from $600 to $5,850, so the right answer changes depending on your facility's demand and power setup.
Quick Take
If you need the lowest listed price and a smaller tank, the used 50-gallon Rheem E50A-9-G-1 is the most affordable entry point. For a new 80-gallon heater on a 277V circuit, the Rheem Rudd ELD80-D sits in the middle of the range at $1,499. The 120-gallon Rheem-Ruud ES120-18-G offers the largest capacity at $3,570, while the AO Smith DSE-120A 200 is a new storage-tank unit with the highest listed price and the most demanding amperage spec at $5,850.
Listed Price Comparison
The price bar below shows where each unit sits relative to the group, from $600 to $5,850.
| Product | Listed Price | Price Bar | Key Spec |
|---|---|---|---|
| Rheem commercial water heater E50A-9-G-1 | USD 600.00 | Used, 50 gal | |
| Rheem Rudd ELD80-D 80 Gallon | USD 1,499.00 | New, 277V, 12.1 kW | |
| Rheem-Ruud ES120-18-G 120 Gal | USD 3,570.00 | New, 120 gal, 18,000W | |
| AO Smith DSE-120A 200 | USD 5,850.00 | New, 120 A, storage tank |
Decision Matrix
| If your priority is... | Consider... | Trade-off |
|---|---|---|
| Lowest listed price | Rheem E50A-9-G-1 | Used condition, 50-gal capacity |
| New 80-gal heater at a moderate price | Rheem Rudd ELD80-D | 277V supply needed |
| Largest tank capacity | Rheem-Ruud ES120-18-G | Higher listed price than smaller new options |
| New AO Smith storage-tank unit | AO Smith DSE-120A 200 | Highest listed price and 120 A supply |
Product Notes
Rheem commercial water heater E50A-9-G-1
At USD 600.00, this used 50-gallon Rheem is the lowest listed price in the comparison. The description mentions 208 single phase or three phase operation, and the model number E50A-9-G-1 appears in the title and attributes. If your facility needs a smaller volume of hot water and you can work with a used unit, this is the most direct way to keep upfront costs down. The limitation is the 50-gallon capacity and used condition: it will not match the volume of the 80- or 120-gallon options, and the condition is explicitly listed as used. For a budget-conscious buyer who has modest hot-water demand, this is the entry-level choice.
Rheem Rudd ELD80-D 80 Gallon Commercial Electric Water Heater 277V 12.1 KW NEW
This new Rheem Rudd heater is listed at USD 1,499.00, making it the middle-priced option in the group. The title confirms an 80-gallon capacity, 277V operation, and 12.1 kW heating power, so it is a straightforward match for facilities that have a 277V circuit available. The 80-gallon tank gives you more hot-water reserve than the used 50-gallon Rheem without jumping to the larger 120-gallon price tier. The limitation is the voltage specificity: because it is built for 277V, it will not suit a standard 240V service unless the supply is converted. If your electrical system can handle 277V, this is a strong new-unit balance between size and listed price.
Rheem-Ruud Es120-18-G 120 Gal 480Commercial Electric Water Heater, Single, Three
Listed at USD 3,570.00, this new Rheem-Ruud unit offers the largest tank capacity in the group at 120 gallons. The listed specs include 18,000W power consumption, three elements, a maximum recovery flow of 149 gph at 50°F, and phase configuration of single or three. The description also references AHRI compliance and CSA certification. If you need a high-volume supply of commercial hot water and want a new unit, this is the capacity leader among the four listings. The limitation is the price step: it costs more than double the 80-gallon Rheem Rudd, so the extra 40 gallons and additional features come with a significant increase in listed price. This is the option for facilities that genuinely need that larger tank.
AO SMITH COMMERCIAL ELECTRIC WATER HEATER MODEL # DSE-120A 200 - NEW IN CRATE
This AO Smith unit is listed at USD 5,850.00, the highest price in the comparison. It is described as new in crate and classified as a storage tank water heater with 120 A amperage and electric features. If you are looking for a new AO Smith commercial electric storage tank unit and your electrical service can support 120 A, this is the premium-priced choice in the group. The limitation is the combination of highest listed price and heavy amperage draw: at 120 A, it likely requires a substantial supply circuit, and the cost is well above the other three options. The title does not state a gallon capacity, so the tank size is identified through the model number DSE-120A 200 rather than a visible number in the listing.
Final Recommendation by Use Case
- Least expensive way into a commercial electric water heater: Rheem commercial water heater E50A-9-G-1 if you can accept a used 50-gallon unit.
- Best fit for 277V services and mid-size demand: Rheem Rudd ELD80-D 80 Gallon, a new unit at $1,499.
- Best fit for maximum capacity in a new unit: Rheem-Ruud ES120-18-G 120 Gal with 18,000W and three elements.
- Best fit for a new AO Smith storage tank with high amp capacity: AO Smith DSE-120A 200 if the 120 A electrical spec and $5,850 listed price work for your project.
