When you’re shopping for a new tankless water heater, the goal is reliable hot water on demand, energy efficiency, and installation flexibility. This guide highlights five top options that balance performance and value for American homes. Best for single-family households, busy households with multiple baths, or spaces needing indoor/outdoor versatility, these models cover gas and electric setups. Below is a quick summary table to compare key specs at a glance.
| Product | Type | Best For | Up To (GPM) | Notes |
|---|---|---|---|---|
| NEW Rinnai RX199iN | Gas Tankless | Large homes with high demand | 11.1 | Indoor/Outdoor, Smart Sense, Versa Vent |
| NEW Rinnai RXP199iN | Gas Tankless | Heavy usage with recirculation | 11.1 | Indoor/Outdoor, built-in recirc pump |
| NEW Rinnai RX180iN | Gas Tankless | Compact, versatile installs | 10 | Indoor/Outdoor, Smart Sense |
| NEW Rinnai RX160iN | Gas Tankless | Smaller homes or fewer fixtures | 9 | Indoor/Outdoor, Versa Vent |
| EcoSmart ECO 18 | Electric Tankless | Energy-conscious setups | Over 2.5 | Self-modulating, 18 kW |
NEW Rinnai RX199iN Condensing Smart Sense
This gas tankless heater supports indoor or outdoor installation using Versa Vent, powered by either propane or natural gas via a Smart Sense control. It delivers up to 11.1 GPM, making it suitable for larger homes with multiple bathrooms. A compact footprint matches modern utility spaces, and the high-efficiency factor (UEF .98) helps reduce energy consumption. The RX-OVC vent cap is required for outdoor use. Includes features like a user-friendly interface and Quick Flush for maintenance.
Best for: Large households with peak hot water needs, especially where outdoor installation is feasible and WiFi control (Controlr) is desired. Better for homes needing strong simultaneous flow and flexibility in fuel choice.
Caution: Outdoor installation requires the RX-OVC vent cap and proper clearance; check local venting codes before setup.
NEW Rinnai RXP199iN Smart Sense Condensing Tankless Water Heater
The RXP199iN mirrors the RX199iN’s capabilities with built-in recirculation to minimize wait times for hot water. It supports indoor/outdoor placement and runs on either propane or natural gas. Its condensed design, Quick Flush, and high efficiency make it a strong pick for households that demand rapid, constant hot water across multiple fixtures. The compact form suits utility closets and tight spaces.
Best for: Families with frequent hot water demands and a need for recirculation to cut wait times. Choose this if you want a built-in circulation feature without extra aftermarket pumps.
Caution: Recirculation adds complexity; ensure the home’s piping layout supports efficient loop benefits.
NEW Rinnai RX180iN Condensing Smart Sense
This model provides up to 10 GPM with the same Versa Vent versatility for indoor or outdoor installation. It’s compact enough for smaller spaces while delivering robust hot water output, ideal for mid-sized homes. As with other Rinnai Smart Sense units, it emphasizes easy operation and maintenance, including the Quick Flush feature and WiFi-ready Controlr module (not included).
Best for: Homes needing strong performance in a slightly smaller system than the RX199iN. Better for spaces where outdoor venting isn’t ideal but indoor mounting is possible.
Caution: Outdoor use requires appropriate venting; verify local venting requirements before installation.
NEW Rinnai RX160iN Condensing Smart Sense
With up to 9 GPM, the RX160iN is a compact entry in the RX series that supports indoor/outdoor installation. It features a high-efficiency design, Quick Flush maintenance, and WiFi control compatibility via Controlr (not included). Its smaller capacity makes it ideal for modest household demands or spaces where a full-sized unit would be excess.
Best for: Smaller homes or apartments where space is limited but gas-powered hot water is still preferred. Choose this if you want Rinnai reliability in a lighter-spec model.
Caution: Ensure your gas line and venting are appropriate for gas-tue capacity; confirm install clearances per local codes.
EcoSmart ECO 18 Electric Tankless
Electric tankless heaters can be a practical alternative when gas lines aren’t available. The EcoSmart ECO 18 uses 18 kW and self-modulating technology to adapt to hot water demand and minimize energy waste. It’s configured for climates where incoming water is 62°F or higher and can support more than 2.5 GPM for select fixtures. Digital temperature control allows fine-tuning in 1-degree increments.
Best for: Homes with reliable 240V electrical supply and lower concurrent hot water needs, such as apartments or small homes. Better for areas with easier electrical upgrades and where gas isn’t an option.
Caution: This model’s output depends on incoming water temperature and electrical service; install considerations include panel capacity and wiring gauge.
Buying Guide
- Fuel type and installation location: Gas models (natural gas or propane) offer higher flow but require venting and, often, outdoor placement options. Electric models avoid venting but demand a robust electrical supply. Indoor/outdoor versuses differ by model—check Versa Vent compatibility and local codes.
- Output capacity and household needs: Match GPM capacity to peak demand. Large homes with multiple bathrooms benefit from higher GPM units (above 9–11 GPM). Smaller homes or apartments can use mid-range or electric options.
- Energy efficiency and operating costs: Look for high UEF or energy factor ratings and features like Quick Flush or self-modulation. These reduce ongoing energy consumption and maintenance costs.
- Maintenance and ease of service: Features like Quick Flush and accessible service points extend unit life. Consider models with WiFi control or remote diagnostics when available for easier upkeep.
- Ventilation and installation considerations: Gas units require proper venting and clearance; outdoor installations typically require vent caps and weatherproof clearances. Electric units need electrical panel capacity and proper wiring.
- Future-proofing and add-ons: Built-in recirculation pumps can reduce water waste. If you anticipate longer wait times for hot water, consider models with recirculation options or quick-return features.
FAQ
- What is a tankless water heater? It heats water on demand, without storing a large tank, which can save space and energy.
- Which is better for a large home: gas or electric tankless? Gas models typically provide higher flow for multiple fixtures, while electric units work well for smaller spaces with solid electrical capacity.
- Do all tankless units require venting? Gas units usually require venting; electric units do not.
- Can a tankless heater supply hot water for multiple bathrooms? Yes, depending on the unit’s GPM rating and your home’s peak hot water demand.
- Is recirculation worth it? Recirculation reduces wait time for hot water at fixtures far from the heater, but it adds system complexity and cost.
- What maintenance is needed? Periodic flushing and service checks keep mineral buildup from reducing efficiency; follow manufacturer guidelines.