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Quick answer from a licensed plumber: For a distant sink with short draws, start with a mini-tank sized around your use and cabinet. GE02P08BAW has a documented cord and compact dimensions; the Ariston Andris 2.5 is another plug-in option. Choose EcoSmart POU 4T only for low-flow use with a suitable dedicated circuit.
For a tight cabinet: Check the GE 2.5-gallon GE02P08BAW on Amazon
If one sink takes minutes to run hot, first establish whether the problem is distance, a fault, or a flow issue at the main heater. A local heater can serve a distant sink, but it adds equipment to maintain. This shortlist compares storage tanks for short draws with a tankless option for restricted flow. Both are point-of-use water heaters: GE says its point-of-use models typically fit under kitchen, bathroom or pantry sinks and connect to a standard 120-volt outlet with the cord included, while EcoSmart’s POU 4T is a point-of-use tankless that needs its own dedicated circuit.
Under-Sink Point-of-Use Water Heaters Compared
| Model | Stored water | Electrical | Body size; check extra installation space |
|---|---|---|---|
| Ariston Andris RS 2.5U | 2.5 gal | 120 V plug-in; confirm circuit | 14-1/4 W × 14-1/4 H in; verify depth |
| GE GE02P08BAW | 2.5 gal | 120 V, 1,500 W; cord included | 13 W × 13 H × 11-1/4 D in |
| GE GE06P08BAW | 6 gal | 120 V, 1,500 W; cord included | 17-1/4 W × 17-3/4 H × 14-1/2 D in |
| EcoSmart POU 4T | No tank | 120 V, 3.5 kW; dedicated 30 A circuit | 7 H × 11 W × 3 D in |
GE figures come from its 2025 product guide; EcoSmart figures come from its exact-model page. Ariston dimensions are from the linked listing and are incomplete for a final cabinet-fit decision. All four listings showed new units in stock on September 27, 2026: Ariston sold by its maker and shipped by Amazon; the other three shipped and sold by Amazon. Availability can change.
Ariston Andris 2.5-Gallon Mini-Tank (Andris RS 2.5U)
2.5-gallon mini-tank · 120 V plug-in design (listing) · copper heating element and enamel-lined tank (Ariston) · external temperature knob
The Ariston Andris RS 2.5U is a small storage heater for a nearby sink. Its listing identifies a 120-volt plug-in design and allows stand-alone or booster use. Ariston describes a copper heating element and an external temperature control on its Andris RS range.
Choose it for short draws, with room to service the tank. The listing gives 14-1/4 inches in width and height but does not give a complete three-dimensional installation envelope; confirm depth and service clearance before ordering. A plug does not establish that your existing outlet and circuit are suitable.
- 120 V plug-in design, per the exact-model listing
- Can serve a sink alone or act as a hot-line booster, per the listing
- External temperature control
- Limited stored supply; temperature falls when the draw exceeds its capacity
- Confirm depth, service access and outlet suitability
- Requires tank maintenance; follow the model manual
Verdict: A candidate for one sink with short draws, after checking the cabinet and electrical supply.
GE Appliances 2.5-Gallon Mini-Tank (GE02P08BAW)
2.5 gallons · 120 V, 1,500 W · cord included · 13 W × 13 H × 11-1/4 D in · 1/2-inch MNPT · stainless element; aluminum anode (GE guide)
GE’s product guide resolves the details missing from the retail listing: GE02P08BAW includes a cord, uses a 1,500-watt element and measures 13 inches wide, 13 high and 11-1/4 deep. The element is stainless steel; the anode is aluminum. Those are separate parts.
Its smaller cabinet dimensions are useful if the drain trap already takes much of the space. Leave room for top connections, the relief-valve discharge and service work. The nominal tank capacity is not a guarantee of 2.5 gallons delivered at a constant temperature.
- Maker documents cord and all three cabinet dimensions
- Wall-mount or freestanding installation
- Stainless heating element
- Small stored supply for longer kitchen draws
- Top connections and service space add to the cabinet requirement
- Anode inspection and tank maintenance still apply
Verdict: The better-documented compact option when cabinet depth and a supplied cord decide the purchase.
GE Appliances 6-Gallon Mini-Tank (GE06P08BAW)
6 gallons · 120 V, 1,500 W · cord included · 17-1/4 W × 17-3/4 H × 14-1/2 D in · 1/2-inch MNPT (GE guide)
GE06P08BAW holds more water than either 2.5-gallon pick. Its larger body needs a careful cabinet check, including the trap, valves and space above the tank.
More storage extends a draw; it does not make this a whole-house heater. GE lists the same wattage as the smaller unit. Choose the tank around measured faucet use, expected draw length and available space, rather than assuming six gallons will cover any kitchen job.
- More stored water than the two 2.5-gallon picks
- Cord and complete dimensions documented by GE
- Wall-mount or freestanding installation
- Needs substantially more cabinet space
- A long draw can still exhaust the stored heat
- Requires access for service and anode maintenance
Verdict: Consider it for longer single-sink draws when the larger tank and service space fit.
EcoSmart POU 4T
Tankless · 3.5 kW · 120 V · maker specifies dedicated 30 A single-pole circuit · 0.25 GPM activation · two 0.35 GPM aerators included
EcoSmart sizes the POU 4T for one low-flow faucet. It has no stored tank to empty, but the water temperature it can produce depends on incoming temperature and flow. A temperature setting alone does not guarantee that outlet temperature in winter.
The maker specifies a dedicated 30-amp single-pole circuit and 10 AWG wiring. It is not a normal plug-in substitute for the mini-tanks. Have a licensed electrician confirm circuit, wiring and installation requirements. At the sink, check aerator compatibility and whether the restricted flow meets your needs.
- No storage-tank recovery wait within its flow and temperature limits
- Compact 7 H × 11 W × 3 D in body
- Thermostatic temperature adjustment
- Dedicated electrical circuit required
- One low-flow faucet, not normal multi-fixture demand
- Cold inlet water can limit useful hot-water output
Verdict: A fit for a genuinely low-flow sink with suitable electrical capacity, not a promise of unrestricted kitchen hot water.
I send an occasional note when a new guide goes up — repairs worth doing yourself, and the parts that actually last. No spam, no course funnel; written by a licensed Georgia plumber.
Cold Feed or Hot-Line Booster?
On a cold feed, the local tank must provide the entire hot-water draw. In a maker-approved booster arrangement, it supplies stored heat while the cooled water in a long hot line passes through. Those are different sizing jobs. Time how long the sink takes to run hot and measure its flow; that gives the installer a practical starting point for the pipe volume to bridge.
For example, a faucet flowing one gallon a minute for two minutes moves about two gallons. That is a pipe-volume estimate, not a promise that a 2.5-gallon tank will maintain your chosen temperature throughout the wait. Mixing, heat loss, inlet temperature and recovery affect delivery.
Check These Before Buying
- Electrical supply: have an electrician confirm the circuit load, grounding and protection. Do not assume an existing switched disposal outlet is suitable.
- Relief and expansion: follow the exact tank manual for the temperature-and-pressure relief valve, discharge route and thermal-expansion control. Never cap a relief outlet. Have a licensed plumber assess these connections.
- Cabinet fit: measure width, height and depth around the trap and valves, then allow space for connections, servicing and any required drain pan.
- Maintenance: allow access to inspect the anode and service the tank as the maker directs. A stainless heating element does not make the tank maintenance-free.
- Use: these are sink heaters. For multiple fixtures, see larger electric tankless choices or our whole-house tankless water heater picks (gas and electric); for a fault elsewhere, start with no-hot-water troubleshooting.
Our tank versus tankless guide explains storage and flow tradeoffs. The T&P relief-valve guide covers valve identification; it is not a substitute for the heater’s installation manual.
FAQ
Can you put a water heater under a sink?
Yes, if the exact model is approved for that location and there is room for the tank or unit, connections, required relief discharge and servicing. Confirm a suitable electrical supply and follow the manufacturer’s installation instructions.
What size under-sink water heater do I need?
Start with faucet flow and the length of a normal draw. A 2.5-gallon tank may suit short sink use; six gallons offers more storage but needs more room. In booster service, account for the cooled water in the pipe before the main heater’s hot water arrives. Nominal capacity is not a guaranteed usable-hot-water volume.
Does an under-sink heater need a dedicated circuit?
Check the exact manual and the existing circuit load. A supplied plug does not prove that a shared disposal or dishwasher circuit is suitable. EcoSmart specifically calls for a dedicated 30-amp circuit for the POU 4T; have a licensed electrician confirm the installation.
Will a 120-volt tankless heater run a kitchen faucet at normal flow?
Do not assume it will. The POU 4T is intended for one low-flow faucet and includes 0.35 GPM aerators. Its achievable water temperature depends on inlet temperature and flow. A mini-tank can support a short draw from stored heat, but must recover afterward.
Can a mini-tank act as a booster on a long hot-water line?
The linked Ariston and GE listings describe booster use. Confirm the model’s permitted inlet temperature and piping arrangement in its manual. The tank must bridge the cool-water volume in the line; it can deliver cooler water if its stored heat is depleted before the main hot water arrives.
Why Trust Plumbing Picks
Plumbing Picks is written by a licensed Georgia journeyman plumber. Every size, rating, dimension and spec on this page comes from the manufacturer pages and documents listed below, which we opened and read, or from the Amazon listing we link; nothing here comes from hands-on testing. Each linked product was shipped or sold by Amazon, new and in stock, when we checked on September 27, 2026. Where a link goes to Amazon we may earn a commission at no extra cost to you. Nobody pays to be included here. More on who writes this and how we pick.
Sources
- GE Appliances: 2025 electric water-heater guide, point-of-use models on printed pages 14–15
- Ariston: Andris RS electric storage water heater
- EcoSmart: POU 4T point-of-use tankless (specifications)
Which One Fits Your Sink?
Use the GE 2.5-gallon or Ariston 2.5-gallon for short draws after checking installation fit. The GE six-gallon adds storage and needs more room. The EcoSmart POU 4T avoids tank recovery only within its low-flow and temperature limits.