Eccotemp i12
Amazon customer rating as of
Tankless Geek editorial score: 3.8/5
The Eccotemp i12 is the design-forward compact of the range: an 80,000 BTU/h, up to 4.0 GPM indoor non-condensing tankless behind a black tempered-glass front with a touchscreen that shows output temperature and live GPM. It shares the 0.7 GPM low-flow ignition of its bigger siblings and runs on a standard 120V cord that powers the exhaust fan, display, and control board. Eccotemp positions it for smaller single-family homes, apartments, condos, and cabins — one to two fixtures at a time.
With an 80,000 BTU burner it comfortably runs a single shower plus a sink in warm climates, dropping toward one fixture in the cold. It's non-condensing (~79% efficiency), so it's inexpensive to buy and needs no condensate drain, but uses more gas per gallon than a condensing unit and must be vented. Like the rest of the line it's certified to 2,000 feet and not recommended above 5,000. Its ~4.1-star rating is a touch better than the larger 45HI — owners like the looks, the compact footprint, and the clear touchscreen for the price.
Key Features
Best Use Cases
Our Verdict
A good-looking, compact indoor propane unit for apartments, condos, cabins, and small homes that need one-to-two fixtures. The tempered-glass touchscreen and low-flow ignition are nice touches at the price. Non-condensing efficiency and the 2,000-foot elevation limit are the trade-offs; size it to a small load and it satisfies.
Technical Specifications
| Input | 25,000–80,000 BTU/h (propane, modulating) |
|---|---|
| Max flow | Up to 4.0 GPM |
| Low-flow ignition | Fires at 0.7 GPM |
| Efficiency | ≈79%, non-condensing |
| Display | Tempered-glass touchscreen (temp + live GPM) |
| Power | 120V cord (fan, display, PCB) |
Specifications verified against the linked source documents. See Sources below.
How much hot water you'll actually get
Usable flow drops as incoming water gets colder. Figures are calculated from rated output (80,000 BTU × 0.79 UEF) and labeled as such — not bench-tested by us.
| Temperature rise | Typical scenario | Usable flow |
|---|---|---|
| 35 °F | Warm climate (75 °F in → 110 °F) | 3.6 GPM |
| 45 °F | Mild climate (65 °F in → 110 °F) | 2.8 GPM |
| 60 °F | Cool climate (50 °F in → 110 °F) | 2.1 GPM |
| 70 °F | Cold climate (40 °F in → 110 °F) | 1.8 GPM |
Usable flow at a 110 °F target: BTU × thermal-eff ÷ (ΔF × 500), capped at the 4.0 GPM maximum (non-condensing ~79%). The 4.0 GPM headline needs warm inlet water.
Pros
Cons
Buy it if…
- Apartments, condos, cabins, and small single-family homes
- One-to-two fixture households in warm/mild climates
- Buyers who want a stylish touchscreen unit on a budget
- Installs with a 120V outlet and proper venting
Skip it if…
- Homes needing 2–3 simultaneous fixtures (step up to the 45HI)
- High-altitude sites above 2,000 feet
- Efficiency-focused buyers wanting condensing performance
Installation Requirements
Professional vs DIY
Best installed by a pro for the gas and vent work; the water and power connections themselves are straightforward.
Gas and electrical work should be done by a licensed professional, and most installs require a permit and must meet local building codes — DIY work can void the manufacturer warranty. Always confirm the unit's own manual for exact clearances, venting, and sizing.
What owners report
Themes summarized from retailer customer feedback (4.1/5 Amazon customer rating, 152 ratings, as of 2026-09-06). These are owner opinions, not our own bench testing.
Owners like the black tempered-glass front and the touchscreen that shows temperature and live flow — a step above utilitarian budget units.
Reviewers in apartments, condos, and cabins find it a tidy, capable fit for one-to-two fixtures.
Satisfaction tracks with sizing it to a small home; pushed to multiple simultaneous fixtures it falls short.
The 120V cord and indoor venting are install requirements owners should plan for, along with the 2,000-foot elevation limit.
Eccotemp i12 FAQ
How many fixtures can the i12 handle?+
About one to two at a time. It delivers up to 4.0 GPM with warm inlet water — a shower plus a sink in mild climates — and roughly one fixture in the cold.
Is it condensing?+
No — it's non-condensing at around 79% efficiency. No condensate drain, but it needs venting and uses more gas per gallon than a condensing unit.
Does it need electricity?+
Yes — a standard 120V cord powers the exhaust fan, touchscreen display, and control board.
How is it different from the 45HI?+
The i12 is smaller and more stylish (80,000 BTU, 4.0 GPM, touchscreen) for one-to-two fixtures; the 45HI is a higher-capacity 150,000 BTU / 6.8 GPM whole-home unit.
How much does cold incoming water cut the i12's flow rate?+
A lot — that's the trade-off of a non-condensing 80,000 BTU/h propane unit. The 4.0 GPM rating assumes a warm inlet and a small temperature rise. Estimated from its rated output, real usable flow is roughly 2.8 GPM at a mild 45 °F rise and closer to 1.8 GPM in cold winters (a 70 °F rise). If you live somewhere with cold groundwater, size the i12 for one fixture at a time and treat it as a point-of-use or warm-climate heater rather than a whole-home unit.
Product sources
Specifications verified 2026-09-06. Manufacturer documents are treated as the primary source for model specifications. Retailer pages are used only for customer ratings and owner-feedback themes.
- Eccotemp i12-LP — Amazon listing (accessed 2026-09-06)
- Eccotemp i12 4.0 GPM LP — Lowe's listing (accessed 2026-09-06)
- Eccotemp i12 — Home Depot owner reviews (accessed 2026-09-06)
Price range from leading retailers
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