Ariston Andris RS 8 Gallon
An 8 gallon tank for a kitchen or utility sink at a low price, with a six-year tank warranty. Plan on hardwiring it.
Amazon $209.99$209.99
The Ariston Andris RS 8 Gallon is the better mini tank water heater overall, rated 3.4 to 2.9. The Ariston Andris RS 8 Gallon leads on warranty and value. The ThermoMate ES800 8 Gallon wins on features. The Ariston Andris RS 8 Gallon costs $60 less ($209.99 vs $269.99).
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.
ThermoMate ES800 8 Gallon
An 8 gallon plug-in tank short enough for an under-counter space. The warranty is short, and the Ariston 8 gallon costs less if you can hardwire.
Amazon $269.99$269.99
Which should you buy?
- Choose the Ariston Andris RS 8 Gallon for warranty (6-year tank, 2-year parts vs 3-year tank, 1-year parts) and value ($26.25 per gallon ($209.99, 8 gal) vs $33.75 per gallon ($269.99, 8 gal)).
- Choose the ThermoMate ES800 8 Gallon for features (plugs into an outlet, relief valve included vs relief valve included, wall bracket included).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every 6 to 10 gallon mini tank water heater; a clear win is highlighted. How we rank explains each one.
| Factor weight | Ariston Andris RS 8 Gallon | ThermoMate ES800 8 Gallon |
|---|---|---|
| Overall rating | 3.4/5 | 2.9/5 |
| Value 30% | 70 $26.25 per gallon ($209.99, 8 gal) | 43 $33.75 per gallon ($269.99, 8 gal) |
| Warranty 30% | 56 6-year tank, 2-year parts | 24 3-year tank, 1-year parts |
| Heating power 15% | 20 1,440 W element | 20 1,440 W element |
| Features 15% | 60 relief valve included, wall bracket included | 75 plugs into an outlet, relief valve included |
| Tank size 10% | 50 8 gal tank | 50 8 gal tank |
Specifications
| Ariston Andris RS 8 Gallon | ThermoMate ES800 8 Gallon | |
|---|---|---|
| Heating | ||
| Tank capacity | 8 gal | 8 gal |
| Element | 1,440 W | 1,440 W |
| Voltage | 120 V | 120 V |
| Current | 12 A | 12 A |
| Electrical connection | Hardwired | Plug-in |
| Recovery (maker figure) | 6.8 gal/hr at 90 °F rise | - |
| Thermostat range | 65 to 167 °F | 50 to 149 °F |
| Price per gallon | $26.25 | $33.75 |
| Installation | ||
| Dimensions (H x W x D) | 17.5 x 17.5 x 15.2 in | 17.7 x 17.7 x 15.4 in |
| Weight | 29.5 lb | 27 lb |
| Water connections | 3/4" NPT (adaptor included) | 1/2" NPT |
| Relief valve included | Yes | Yes |
| Wall bracket included | Yes | - |
| Warranty | ||
| Tank | 6 years | 3 years |
| Parts | 2 years | 1 year |