Ecosmart 1-Gallon 120V Electric Mini Tank Water Heater
✅ PROS
- Delivers hot water within 15-20 minutes with a 1440W heating element, eliminating the long wait from a distant main tank
- Compact footprint (12.5 inch " tall, 12.75 inch " wide, 10.5 inch " deep) fits under most sinks; includes a 6-ft power cord
- Copper heating element resists scale buildup better than stainless alternatives in hard-water areas
❌ CONS
- 1-gallon capacity runs out fast — roughly 1-2 minutes of continuous hot water before reheating
- Requires a dedicated 15-amp circuit; sharing the outlet with a garbage disposal or other appliance will trip breakers
- No temperature display or dial on the unit itself — you'll need to adjust via the thermostat behind the front panel
The Verdict
The 1-Gallon Solution: When a Full Tank Is Overkill
If you’ve ever stood at a bathroom sink for 45 seconds waiting for hot water while brushing your teeth, you already know the problem this Ecosmart solves. The 1-gallon 120V mini tank heater sits right under your sink and delivers hot water almost instantly — no more running the tap for a minute straight while the main tank’s supply makes its way through cold pipes.
But here’s the thing: this isn’t a whole-house solution. It’s a targeted fix for a specific annoyance. Let’s break down whether it’s the right fix for you.
What You Actually Get
The unit measures 12.5 inches tall, 12.75 inches wide, and 10.5 inches deep — roughly the size of a small carry-on bag folded in half. It comes with a 6-foot power cord, a pressure relief valve, and mounting brackets. You’ll need to supply your own water connections (1/2-inch NPT fittings standard) and the mounting hardware for your specific wall studs is included.
One thing shoppers consistently note: the installation isn’t hard, but it’s not plug-and-play either. You’re adding a hardwired appliance. The unit draws 12 amps at full load, which means it must be on a dedicated 15-amp circuit. Several reviewers mention this after the fact. One wrote:
“Wish I’d known about the dedicated circuit before I blew the breaker three times. Once I ran a separate line, it’s been flawless.”
Real-World Performance
The 1440W heating element brings the 1-gallon tank from cold to 125°F in about 15-20 minutes. Once hot, it maintains temperature. The key number to understand: you get about 1-2 minutes of continuous hot water before the tank empties and needs to reheat. For washing hands, shaving, or rinsing a brush — perfect. For filling a pot or a long shower — absolutely not.
Where this unit shines is in scenarios like:
- A half-bath or guest bathroom far from the main water heater
- A workshop sink where you need hot water for cleaning tools
- An RV or tiny home setup (users confirm it runs fine on residential 120V)
The copper heating element is a thoughtful touch. In hard-water areas, copper sheds scale more effectively than stainless steel, meaning less maintenance and longer life. Multiple long-term reviewers (2+ years of use) report no element failures.
Where It Falls Short
The capacity limitation is the elephant in the room. If you have multiple people using the same sink in quick succession, you’ll wait for reheats. Expect a 15-minute recovery time between uses.
The lack of a user-accessible temperature control is another minor gripe. The thermostat is behind the front panel, which is fine for a set-and-forget installation, but if you want to adjust from 120°F to 140°F, you’re unscrewing the cover. Not a dealbreaker, but worth knowing.
A few buyers also mention the unit hums slightly during heating cycles. It’s not loud — more of a low electrical buzz — but if you’re mounting it directly under a sink in a quiet bathroom, you’ll notice it.
Who Should Buy This
Buy it if:
- You have a sink that takes 60-90 seconds to get hot water from the main heater
- You need a compact, reliable hot water source for a workshop, garage, or laundry room
- You’re handy enough to run a dedicated circuit or can budget for an electrician
Skip it if:
- You need hot water for anything beyond hand-washing or small tasks
- You can’t add a dedicated circuit to the location
- You’re expecting this to replace a traditional water heater
FAQ
Q: Can this run on a standard 15-amp outlet? A: Yes, but only if that outlet is on a dedicated circuit. If other appliances share the circuit, you’ll trip breakers. Most installations require a new circuit run.
Q: How long does it take to reheat after running out? A: From fully cold to 125°F takes 15-20 minutes. If you only used half the tank, you’re looking at 7-10 minutes for usable hot water.
Q: Does it come with the pressure relief valve installed? A: It ships with the valve included but not pre-installed — you’ll mount it during setup. The manual covers this clearly, and it’s a 10-minute job.
The Verdict
Buy it if you have a specific sink with slow hot water delivery and you can manage the electrical requirements. It’s a reliable, well-built fix at a reasonable price point. Skip it if you can’t run a dedicated circuit or you’re expecting more than a gallon of hot water at a time.
At 4.2/5 stars, this is a solid, honest performer — just make sure you understand exactly what a 1-gallon tank can and can’t do before you buy. For its intended purpose, it does the job admirably.
Where to Buy
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Last updated: 2026-08-06. Ratings and prices current as of review date. Verify on Amazon before purchasing.