Quick Answer: The best propane tankless water heater for a whole home is the Rinnai Sensei RX199iN — the condensing 199,000 BTU unit that replaced the RU199iP, rated up to 11.1 GPM (warm inlet) at a 0.98 UEF with a 15-year heat-exchanger warranty, and its Adaptive Gas Valve runs on propane or natural gas with no conversion kit. For the best value at retail, the Rheem Performance Platinum ECOH200DVLP delivers 9.5 GPM and 199,900 BTU with EcoNet WiFi, and the Takagi T-H3-DV-P is the best mid-price condensing unit. For a cabin, RV, or off-grid setup, the Camplux 2.64 GPM portable runs on 3–110 psi with no electricity, while the Eccotemp L10 is the budget outdoor pick. Every GPM figure below assumes a warm inlet — cold winter water lowers real flow.
Last updated July 29, 2026 — corrected the RV/off-grid pick’s model number (Camplux’s 2.64 GPM/68,000 BTU battery-ignition portable is the BW264-N, not the AY132, which is Camplux’s smaller 1.32 GPM unit) and re-verified its current street price against Camplux, Lowe’s, and Home Depot listings ($180 was stale; it’s now $230–$270).
Propane (LP) tankless water heaters split into two very different buyers: homeowners replacing a whole-home heater with no natural-gas line, and off-grid, RV, and cabin users who want endless hot water from a portable propane tank. We compared both — the condensing whole-home units from Rinnai, Rheem, and Takagi, and the portable outdoor units from Camplux and Eccotemp — on flow rate (GPM), BTU output, efficiency (UEF), and price, so you buy the right propane heater for your install.
Our top picks at a glance
| Model | Best for | Type | Max Flow / BTU | Efficiency | Warranty | Price |
|---|---|---|---|---|---|---|
| Rinnai Sensei RX199iN (dual-fuel NG/LP) | Best overall (whole home) | Condensing indoor/outdoor | 11.1 GPM · 199k BTU | 0.98 UEF | 15 yr | ~$1,530–1,725 |
| Rheem Performance Platinum ECOH200DVLP | Best retail / DIY value | Condensing indoor | 9.5 GPM · 199.9k BTU | ENERGY STAR | 12 yr | ~$1,200 |
| Takagi T-H3-DV-P | Best mid-price | Condensing indoor | 10 GPM · 199k BTU | High-eff | 15 yr | ~$1,250 |
| Rinnai V53DeP | Best small-home value | Non-condensing | 5.3 GPM · 120k BTU | 0.81–0.82 EF | 10 yr | ~$700 |
| Camplux 2.64 GPM (BW264-N) | Best RV / off-grid | Portable outdoor | 2.64 GPM · 68k BTU | N/A | 2 yr | ~$230–$270 |
| Eccotemp L10 | Best budget portable | Portable outdoor | 2.6 GPM · 74.5k BTU | N/A | 1–2 yr | ~$150 |
By the numbers
- ~91,500 BTU of energy in a single gallon of propane, so a full-fire 199,000 BTU whole-home unit uses roughly 2.2 gallons per hour — but only while hot water is actually running. — U.S. propane energy content (DOE/industry)
- 9.5 GPM · 199,900 BTU on the Rheem Performance Platinum propane unit, enough for 2–3 simultaneous fixtures in most climates. — Rheem
- 2.64 GPM at 3–110 psi on the Camplux portable — it fires on very low water pressure, which is why it’s the go-to for off-grid and RV use. — Camplux (via Bob Vila)
- 24–34% more efficient than a storage tank for homes using 41 gallons/day or less (8–14% for high-use homes) — the efficiency case applies to propane just as it does to natural gas. — U.S. Department of Energy
1. Rinnai Sensei RX199iN — Best Overall (Whole Home)
Rinnai Sensei RX199iN Condensing Tankless (Natural Gas or Propane)
- 199,000 BTU condensing burner rated up to 11.1 GPM on a warm inlet — comfortably runs 2–3 fixtures at once.
- 0.98 UEF with inexpensive PVC venting; Bluetooth setup via the Rinnai Central app.
- Rinnai's Adaptive Gas Valve adjusts to natural gas or propane automatically — no LP conversion kit and no separate propane SKU, per Rinnai.
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The Sensei RX199iN is the current version of the unit we used to recommend here as the RU199iP — Rinnai rebranded its flagship condensing RU Series as the Sensei RX Series, bumped efficiency to a 0.98 UEF, and stretched the heat-exchanger warranty to 15 years. The biggest change for propane buyers: the RX’s Adaptive Gas Valve runs on natural gas or LP out of the box, so there’s no separate “iP” SKU to hunt down and no conversion kit to install. At $1,530–$1,725 street it’s also cheaper than the comparable Navien, per a 2026 master-plumber review by Mother. Every current Rinnai model is ranked in our best Rinnai tankless water heater guide.
2. Rheem Performance Platinum ECOH200DVLP — Best Retail / DIY Value
Rheem Performance Platinum ECOH200DVLP-2 Propane Tankless
- Condensing 199,900 BTU, 9.5 GPM, ENERGY STAR certified with EcoNet WiFi.
- Factory propane (LP) model — convertible-listed for indoor or outdoor installation.
- Sold at major retailers, so it's the easiest premium propane unit to buy and get parts for yourself.
Rheem’s retail Performance Platinum “ECOH” line brings condensing efficiency, WiFi, and 9.5 GPM to the home-improvement aisle at a lower price than the Rinnai. The propane ECOH200DVLP is the same idea packaged for retail buyers and DIY-friendly installs — don’t confuse it with the pro RTGH series. It’s our value pick for a whole-home propane upgrade.
3. Takagi T-H3-DV-P — Best Mid-Price
Takagi T-H3-DV-P Condensing Propane Tankless
- 10 GPM and 199,000 BTU on propane — strong flow for a family of 4–5.
- Condensing efficiency from a respected pro brand — note Takagi is an A.O. Smith brand, not a Rinnai one, and its own spec sheet lists this model as not ENERGY STAR qualified.
- 15-year heat-exchanger warranty — the longest here on a whole-home unit.
Takagi (owned by Rinnai) offers pro-grade condensing units at value pricing. The T-H3-DV-P pairs 10 GPM and a 15-year warranty for around the same money as a mid-tier Rheem — an excellent choice for a mid-size family that wants an LP workhorse without the flagship badge. Confirm the “-P” propane suffix when ordering.
4. Rinnai V53DeP — Best Small-Home Value
Rinnai V53DeP Non-Condensing Propane Tankless
- 5.3 GPM and 120,000 BTU — right-sized for 1–2 bath homes, condos, and additions.
- Non-condensing (~0.81–0.82 EF) keeps the purchase price low; needs stainless-steel venting.
- Proven Rinnai reliability and parts availability at a fraction of the flagship price.
Not every home needs 199,000 BTU. The V53DeP is Rinnai’s entry non-condensing propane unit and the smart buy for a smaller household that doesn’t run three showers at once. You trade condensing efficiency and PVC venting for a much lower price — a sensible call when peak demand is modest. Size up to the RX199iN or a 199k unit only if you truly need the extra simultaneous flow.
5. Camplux 2.64 GPM (BW264-N) — Best RV & Off-Grid
Camplux 2.64 GPM Portable Propane Tankless (BW264-N)
- 2.64 GPM and 68,000 BTU from a standard propane tank — endless hot showers off-grid.
- Fires on water pressure as low as 3 psi (up to 110 psi), ideal for RV pumps and gravity feeds.
- D-cell battery ignition — no 120V power or gas line required.
For cabins, hunting camps, van builds, and RVs, the Camplux is the propane heater to get. It needs no electrical hookup and lights on very low water pressure, so it works where whole-home units can’t. It’s not for a full house, but for a single shower or outdoor kitchen far from the grid, nothing beats the value. Always run portable propane units outdoors or vented, never inside a closed space. Outfitting a camper specifically? See our best RV tankless water heater roundup for drop-in units from Fogatti, Camplux, and Furrion.
6. Eccotemp L10 — Best Budget Portable
Eccotemp L10 Portable Propane Tankless
- 2.6 GPM and 74,500 BTU — a touch more burner than the Camplux for a lower price.
- Battery ignition, garden-hose fittings, and an included showerhead for outdoor use.
- The cheapest way into propane on-demand hot water for camping and washdown stations.
Eccotemp is the budget name in portable propane, and the L10 is its most popular outdoor model. It’s the pick when you want hot water at a campsite, dog-wash, or outdoor kitchen for as little money as possible. Like all portable LP heaters, use it outdoors only and store the battery ignition dry.
How to choose a propane tankless water heater
- Whole-home vs portable: For a house with plumbing, buy a fixed condensing unit (Rinnai/Rheem/Takagi). For a cabin, RV, or outdoor use, buy a portable (Camplux/Eccotemp) that needs no electricity.
- Buy the LP (propane) SKU: Propane runs at higher pressure than natural gas. Buy the factory propane model (iP / -P / DVLP) or a manufacturer-listed convertible — never run a natural-gas unit on propane un-converted.
- Condensing vs non-condensing: Condensing (~0.93–0.97 UEF, cheap PVC venting) costs more upfront but runs cheaper; non-condensing (~0.81–0.82 EF) is cheaper to buy but needs stainless venting — full breakdown in our condensing vs non-condensing comparison.
- Size by GPM: Most 2–3 bath homes want 7–9 GPM at peak (a 199k BTU unit); RVs and single showers are fine at 2.6–4 GPM. Cold inlet water lowers real flow, so size up in the North.
- Propane supply & venting: A 199k BTU unit needs adequate propane regulator sizing and proper venting. Have an installer confirm gas sizing before you buy.
The bottom line
For most homes with no natural-gas line, the Rinnai Sensei RX199iN is the best propane tankless water heater: 11.1 GPM warm-inlet flow, 0.98 UEF condensing efficiency, a 15-year heat-exchanger warranty, and a dual-fuel Adaptive Gas Valve that runs on LP with no conversion kit. Want retail-easy value? The Rheem Performance Platinum ECOH200DVLP and Takagi T-H3-DV-P deliver near-flagship performance for less — though the Takagi brand was discontinued by the manufacturer on December 31, 2025, so read our Takagi tankless guide before you buy one, and the Rinnai V53DeP is the smart small-home pick. Going off-grid or outfitting an RV? The Camplux 2.64 GPM and budget Eccotemp L10 give you endless propane hot water with no electricity. Mounting on an exterior wall to skip venting entirely? See our best outdoor tankless water heater guide for the natural-gas wall-mount picks. Not sure propane is even the right fuel? Compare it in our electric vs gas tankless guide, or see all fuels in our best tankless water heater roundup.