Ariston Andris RS 2.5 Gallon
A low-priced 2.5 gallon plug-in tank for a single sink, with a six-year tank warranty. It is the value pick among the small tanks.
Amazon $159.99$159.99
2.5 gal1,440 WPlug-in
2.3/5
A compact 2.5 gallon plug-in tank with a freeze setting, suited to a cabin or garage sink. The warranty is short for the price.
- 2.5 galTank
- 1,440 WElement
- Plug-inPower
- 3 yearsTank warranty
Check price at Amazon$199.99
Price checked November 9, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Plugs in with a 2 ft cord, no wiring needed
- Freeze-protection setting keeps the tank from freezing in a cold cabin or garage
- Short 13 in height fits low cabinets
Cons
- Three-year tank warranty, half what Ariston and Rheem give
- Two-foot cord needs an outlet close to the tank
The ThermoMate ES mini tank family
Every ThermoMate ES mini tank model we rank, smallest first. Ratings compare each against its own size.
| Model | Tank | Rating | Price |
|---|---|---|---|
| ThermoMate ES250 2.5 Gallon (this one) | 2.5 gal | 2.3/5 | $199.99 |
| ThermoMate ES400 4 Gallon | 4 gal | 3.2/5 | $220.99 |
| ThermoMate ES700 6.5 Gallon | 6.5 gal | 2.6/5 | $239.99 |
| ThermoMate ES800 8 Gallon | 8 gal | 2.9/5 | $269.99 |
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
Specifications
| Model number | ES250 |
|---|---|
| Heating | |
| Tank capacity | 2.5 gal |
| Element | 1,440 W |
| Voltage | 120 V |
| Current | 12 A |
| Electrical connection | Plug-in |
| Thermostat range | 50 to 149 °F |
| Price per gallon | $80 |
| Installation | |
| Dimensions (H x W x D) | 12.9 x 12.9 x 11.5 in |
| Weight | 15.4 lb |
| Water connections | 1/2" NPT |
| Relief valve included | Yes |
| Warranty | |
| Tank | 3 years |
Alternatives in this size
Rheem Mini-Tank 2.5 Gallon
A slim 2.5 gallon plug-in tank from Rheem for one sink. It matches the Ariston on warranty but costs more.
Amazon $218.99$218.99
2.5 gal1,440 WPlug-in
Stiebel Eltron SHC 2.5
A German-made 2.5 gallon plug-in tank for one bathroom or kitchen sink. It costs more than the imports but carries a six-year tank warranty.
Amazon $212.91$212.91
2.5 gal1,300 WPlug-in
Compare
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