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
The Ariston Andris RS 2.5 Gallon is the better mini tank water heater overall, rated 3.2 to 2.8. The Ariston Andris RS 2.5 Gallon leads on value. The Ariston Andris RS 2.5 Gallon costs $59 less ($159.99 vs $218.99).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
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
Which should you buy?
- Choose the Ariston Andris RS 2.5 Gallon for value ($64 per gallon ($159.99, 2.5 gal) vs $87.60 per gallon ($218.99, 2.5 gal)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every 2.5 to 4 gallon mini tank water heater; a clear win is highlighted. How we rank explains each one.
| Factor weight | Ariston Andris RS 2.5 Gallon | Rheem Mini-Tank 2.5 Gallon |
|---|---|---|
| Overall rating | 3.2/5 | 2.8/5 |
| Value 30% | 42 $64 per gallon ($159.99, 2.5 gal) | 3 $87.60 per gallon ($218.99, 2.5 gal) |
| Warranty 30% | 56 6-year tank, 2-year parts | 56 6-year tank, 2-year parts |
| Heating power 15% | 20 1,440 W element | 20 1,440 W element |
| Features 15% | 100 plugs into an outlet, relief valve included, wall bracket included | 100 plugs into an outlet, relief valve included, wall bracket included |
| Tank size 10% | 0 2.5 gal tank | 0 2.5 gal tank |
Specifications
| Ariston Andris RS 2.5 Gallon | Rheem Mini-Tank 2.5 Gallon | |
|---|---|---|
| Heating | ||
| Tank capacity | 2.5 gal | 2.5 gal |
| Element | 1,440 W | 1,440 W |
| Voltage | 120 V | 120 V |
| Current | 12 A | 12 A |
| Electrical connection | Plug-in | Plug-in |
| Recovery (maker figure) | 6.8 gal/hr at 90 °F rise | 15 min at 60 °F rise |
| Thermostat range | 65 to 161 °F | 50 to 140 °F |
| Price per gallon | $64 | $87.60 |
| Installation | ||
| Dimensions (H x W x D) | 14.2 x 14.2 x 10.8 in | 17 x 10.9 x 10.9 in |
| Weight | 15.5 lb | 17.6 lb |
| Water connections | 1/2" NPT | 1/2" NPT |
| Relief valve included | Yes | Yes |
| Wall bracket included | Yes | Yes |
| Warranty | ||
| Tank | 6 years | 6 years |
| Parts | 2 years | 2 years |