Quick Answer: The best Rheem tankless water heater for most gas homes is the IKONIC (sold as ECOHS200iN at Home Depot, RTGH-S11i through pro supply) — a condensing unit rated up to 11.2 GPM on a warm inlet at a 0.96 UEF with built-in WiFi and LeakGuard leak detection, listed at $1,799 and recently marked down to $1,439 at Home Depot. The Performance Platinum ECOH200DVELN-3 ($1,199, 9.5 GPM, 0.93 UEF) is the best-value condensing pick, and the Performance Plus ECO200DVELN-3 ($1,057) is the budget gas play. Going electric? The 24 kW RTEX-24/RETEX-24 (from $549) is the whole-home warm-climate pick and the RTEX-13 ($255–$365) covers a single fixture. Every GPM figure below assumes a warm inlet — cold winter water lowers real flow.
Rheem sells more tankless water heaters through big-box retail than any other brand — but its catalog is genuinely confusing, because almost every unit exists twice: once as a retail SKU at Home Depot (RETEX, ECO, ECOH, ECOHS) and once as a pro SKU through plumbing supply (RTEX, RTGH). This guide ranks every current residential Rheem line and decodes the naming so you can compare apples to apples — and spot when the “different” model a supplier quotes you is the same machine with a different sticker.
Rheem’s model names, decoded
Rheem runs two parallel catalogs for the same hardware platforms:
- Retail (Home Depot): Performance = RETEX electric · Performance Plus = ECO gas non-condensing · Performance Platinum = ECOH gas condensing · IKONIC = ECOHS super-high-efficiency condensing flagship.
- Pro (plumbing supply): Professional Classic = RTEX electric · Professional RTGH = gas condensing · IKONIC’s pro twin = RTGH-S11i.
- The ratings differ even when the hardware doesn’t. Rheem rates the pro RTEX-24 at up to 5.9 GPM in warm climates, while Home Depot lists the retail RETEX-24 at 4.68 GPM — same 24 kW class, different temperature-rise assumptions in the spec sheet.
- Suffixes: DV = direct vent (indoor) · X = outdoor · N = natural gas · P/LP = propane · “-3” = current generation on retail gas models.
Our top picks at a glance
| Model | Best for | Type | Max Flow (warm inlet) | Efficiency | Price |
|---|---|---|---|---|---|
| IKONIC ECOHS200iN | Best overall | Gas condensing | 11.2 GPM · 199.9k BTU | 0.96 UEF | $1,799 list ($1,439 sale) |
| Performance Platinum ECOH200DVELN-3 | Best value condensing | Gas condensing | 9.5 GPM · 199.9k BTU | 0.93 UEF | $1,199 |
| Performance Plus ECO200DVELN-3 | Best budget gas | Gas non-condensing | 9.5 GPM · 199.9k BTU | Non-condensing (0.81–0.82 class) | ~$1,057 |
| RTEX-24 / RETEX-24 | Best whole-home electric | Electric 24 kW | Up to 5.9 GPM (Rheem, warm climate) | ~99% at unit | $549 (RETEX) / ~$650 (RTEX) |
| RTEX-13 | Best point-of-use electric | Electric 13 kW | Up to 3.17 GPM | ~99% at unit | ~$255–$365 |
| RTGH-S11i / RECTGH-SR11iN | Best pro install / recirculation | Gas condensing (pro) | 11.2 GPM · 199.9k BTU | 0.96 UEF | ~$1,800–$2,500 |
By the numbers
- 0.96 UEF on the IKONIC condensing platform — ENERGY STAR certified and up to a 36% reduction in energy use versus a standard 0.61-UEF 50-gallon tank, per Rheem. — Rheem
- $1,799 list, recently $1,439 on sale for the IKONIC ECOHS200iN at Home Depot — a $360 markdown that turns the flagship into a near-value pick. — Home Depot, July 2026
- 5.9 GPM (Rheem, warm climate) vs 4.68 GPM (Home Depot listing) for the same 24 kW electric platform (RTEX-24 vs RETEX-24) — the clearest published example of why you should size by temperature rise, not the number on the box. — Rheem / Home Depot
- 9.5 GPM at a 35°F rise and a 0.93 UEF for the Performance Platinum ECOH200DVELN-3, with EcoNet WiFi and LeakGuard built in. — Rheem spec sheet
- Up to 34% energy/cost savings in whole-home electric installs claimed for the self-modulating RETEX line versus a standard electric tank. — Rheem / Home Depot
1. Rheem IKONIC ECOHS200iN — Best Overall
Rheem IKONIC Super High Efficiency Condensing Gas Tankless (ECOHS200iN)
- Rheem's condensing flagship: up to 11.2 GPM on a warm inlet — enough for 2–3 simultaneous fixtures in most climates.
- 0.96 UEF, ENERGY STAR certified, PVC-ventable, and eligible for the federal 25C tax credit (up to $600).
- Built-in EcoNet WiFi with real-time monitoring plus LeakGuard Plus, which watches flow patterns and can shut the unit down before a leak becomes water damage.
Get your tankless heater and fittings in two days — try Amazon Prime free for 30 days.
The IKONIC is Rheem’s answer to the Rinnai Sensei RX and Navien NPE-2 flagships, and it’s the Rheem gas tankless we’d buy: 0.96 UEF condensing efficiency, indoor/outdoor installation, and the best control stack in the class — EcoNet WiFi is standard, and LeakGuard leak detection is something neither Rinnai nor Navien includes at this price. At the $1,799 list price it’s a fair fight with the Rinnai RX199iN ($1,530–$1,725 street, 0.98 UEF, 15-year warranty); at the recent $1,439 Home Depot sale price, the IKONIC is simply the better deal. Buying through a plumber? Ask for the pro twin, the RTGH-S11i — it’s the same platform.
2. Rheem Performance Platinum ECOH200DVELN-3 — Best Value Condensing
Rheem Performance Platinum Smart Condensing Gas Tankless (ECOH200DVELN-3)
- Condensing efficiency (0.93 UEF) and PVC venting at a mid-pack price — $1,199 at Home Depot.
- 9.5 GPM at a 35°F rise covers a 2–3 bath home in warm and moderate climates.
- Same EcoNet WiFi and LeakGuard protection as the IKONIC; indoor or outdoor install; propane version is the ECOH200DVELP-3.
For most gas households, this is the sweet spot in Rheem’s catalog: you keep the condensing efficiency, the cheap PVC venting, the 25C tax-credit eligibility, and the smart features, and you give up about 1.7 GPM of warm-inlet headroom versus the IKONIC for $600 less at list. If your realistic peak is two showers, the Performance Platinum will never feel small. It’s also the unit we shortlisted in our best gas tankless roundup as the strongest retail-availability pick — no plumbing-supply account required.
3. Rheem Performance Plus ECO200DVELN-3 — Best Budget Gas
Rheem Performance Plus Smart Non-Condensing Gas Tankless (ECO200DVELN-3)
- Full 199,900 BTU burner and 9.5 GPM warm-inlet rating for $1,057.39 at Home Depot — the cheapest whole-home gas Rheem.
- Non-condensing: cheaper to buy, but indoor installs need stainless or concentric venting rather than PVC — price the vent kit into your budget.
- Still gets built-in EcoNet WiFi, rare at this price; outdoor version (ECO200XELN-3) skips venting entirely.
The Performance Plus is the classic non-condensing trade: about $140 cheaper than the Performance Platinum up front, but it wastes more heat (non-condensing units run in the 0.81–0.82 UEF class) and its hot exhaust demands pricier venting indoors. The math that decides it is the vent run: mounting it outdoors (the ECO200XELN-3 variant) erases the venting cost and makes this the cheapest whole-home gas path in Rheem’s lineup — the same logic our tankless vs tank guide applies to total installed cost rather than sticker price.
4. Rheem RTEX-24 / RETEX-24 — Best Whole-Home Electric
Rheem RTEX-24 (pro) / RETEX-24 (retail) 24 kW Electric Tankless
- Rheem's 24 kW electric platform: up to 5.9 GPM in warm climates per Rheem — Home Depot lists its retail RETEX-24 twin at 4.68 GPM under a bigger assumed temperature rise.
- Self-modulating: draws only the power the flow demands; ~99% of the energy goes into the water, with no venting at all.
- Electrical reality check: needs three 40A double-pole breakers (~100A of capacity) on a 240V panel — get an electrician's quote first.
Rinnai and Navien don’t make electric tankless units — Rheem does, and dominates the category. The 24 kW RTEX-24 (or its retail twin RETEX-24 at $549 from Home Depot) is the pick for 1–2 bath homes in warm and moderate climates: no gas line, no venting, and an install that’s often half the cost of gas. The catch is winter physics — at a northern 60–70°F temperature rise, 24 kW supports roughly one to two fixtures, not a whole busy household. Cold-climate whole-home buyers should step up to the 36 kW RTEX-36 (roughly 150A of service) or stay with gas; our best electric tankless roundup walks the full sizing ladder. Rheem’s closest value rival here is the lifetime-warranty EcoSmart ECO 27, which lands at nearly the same ~$500 price.
5. Rheem RTEX-13 — Best Point-of-Use Electric
Rheem RTEX-13 13 kW Electric Tankless
- Up to 3.17 GPM per Rheem — a single shower or sink, or a whole small warm-climate apartment.
- 54A draw on a single 60A double-pole breaker makes it the easiest Rheem electric to retrofit.
- Digital thermostat adjustable in 1°F steps from 80–140°F; 5-year heating-chamber warranty.
The RTEX-13 is the unit that made Rheem the default name in electric tankless: around $255–$365 street, one breaker slot, and endless hot water for a bathroom, garage sink, or accessory apartment. It’s a point-of-use heater first — pair it with the fixture it serves and it shines; ask it to run a northern two-bath house and it will disappoint. The retail twin is the RETEX-13 (2.54 GPM per Home Depot’s colder-rise rating — the same two-catalog math as the 24 kW pair).
6. Rheem RTGH-S11i / RECTGH-SR11iN — Best Pro Install & Recirculation
Rheem IKONIC Pro (RTGH-S11i) / with Recirculation (RECTGH-SR11iN)
- The IKONIC platform in pro trim, sold through plumbing supply — same 11.2 GPM, 0.96 UEF condensing performance.
- The RECTGH-SR11iN adds a built-in recirculation pump for instant-at-the-tap hot water — Rheem's answer to Rinnai's RXP and Navien's NPE-A2.
- Typically $1,800–$2,500 depending on channel; your plumber's quote may name this SKU instead of ECOHS200iN — it's the same family.
If a contractor is doing the install, the quote will likely say RTGH, not ECOHS — don’t let the unfamiliar SKU push you into thinking it’s a different (or older) machine. The one meaningful upgrade in the pro channel is the recirculation version: the RECTGH-SR11iN’s built-in pump kills the cold-water-sandwich wait, which is the single most-noticed comfort difference in a tankless conversion.
How to choose a Rheem tankless water heater
- Decode the SKU first: RETEX/ECO/ECOH/ECOHS = retail (Home Depot); RTEX/RTGH = pro. Same platforms, different stickers and sometimes different advertised GPM — compare kW and BTU, not marketing flow numbers.
- Gas: condensing is usually worth it. The 0.93–0.96 UEF ECOH/ECOHS units vent in cheap PVC and qualify for the federal 25C credit (up to $600); the ~$140 saved on a non-condensing ECO can vanish into its stainless vent kit.
- Electric: size by amperage, then climate. 13 kW (54A) = one fixture; 24 kW (three 40A breakers) = warm-climate 1–2 baths; 36 kW (~150A) = cold-climate whole home. Panel upgrades cost more than the heater — check before you buy.
- Size by winter, not the box: Rheem’s own numbers show the same 24 kW unit rated 5.9 GPM (warm climate) or 4.68 GPM (colder assumed rise). Use your coldest-month inlet temperature.
- Match the fuel suffix: N = natural gas, P/LP = propane on gas models — Rheem gas units don’t convert with a switch.
The bottom line
For most gas homes, the Rheem IKONIC (ECOHS200iN) is the best Rheem tankless water heater — 11.2 GPM warm-inlet flow, 0.96 UEF, and WiFi plus LeakGuard as standard, especially when it’s on sale near $1,439. The Performance Platinum ECOH200DVELN-3 at $1,199 is the value condensing play, and the Performance Plus covers tight budgets. Going electric, the RTEX-24/RETEX-24 from $549 and the point-of-use RTEX-13 are the class defaults — a category where Rheem barely has competition from the other big gas brands. Comparing across brands? Start with our best tankless water heater roundup for every fuel type, the Rinnai lineup guide for the flagship rivalry, or our electric vs gas comparison if you’re not sure which fuel fits your home.