10 Best Tankless Water Heaters With Leak Detection for 2026: Reliable Hot Water With Smarter Protection

If you want endless hot water without giving up peace of mind, tankless water heaters with leak detection are a smart place to start. They help reduce the risk of water damage while delivering efficient, on-demand performance.

Below, we’ve narrowed the field to 10 standout options for different fuel types, flow rates, and installation needs so you can quickly find the right match for your home.

Best 10 Tankless Water Heaters with Leak Detection Picks for 2026

Whole-Home Smart Gas Pick – MIZUDO 199,000 BTU Indoor Tankless

If you want tankless water heaters with leak detection features in a smart whole-home setup, the MIZUDO indoor natural gas model is built for high-demand households that need steady hot water across multiple fixtures. It delivers up to 10.3 GPM, supports low-flow activation, and adds WiFi/app controls with instant abnormal alerts for easier monitoring.

Best For: Busy homes wanting a high-output indoor gas unit with app-based monitoring and whole-house coverage.

Pros:

• Up to 10.3 GPM and 199,000 BTU for 2–3 bathrooms plus kitchen and laundry use
• ±1°F temperature control with a wide range up to 149°F
• Smart WiFi control with app status checks and instant abnormal alerts
• CSA certified for indoor installation with compact wall-mounted design

Cons:

• Professional installation is recommended
• Not recommended for elevations above 3,000 feet
• Leak detection is not explicitly listed as a dedicated feature

This is a strong choice if you value capacity, temperature stability, and remote alerts in one package. It is less about compact simplicity and more about whole-home performance with connected oversight.

Versatile Condensing Choice – Rinnai RX130iN Smart Sense

Among tankless water heaters with leak detection-minded smart features, the Rinnai RX130iN stands out for flexibility and efficiency rather than a dedicated leak sensor. It can be installed indoors or outdoors, runs on natural gas or propane, and offers up to 7.1 GPM with condensing performance for compact homes that want an adaptable system.

Best For: Homeowners who want a flexible indoor/outdoor gas tankless heater with strong efficiency and brand-backed support.

Pros:

• Indoor or outdoor installation with Versa Vent
• Works with natural gas or propane
• Up to 7.1 GPM with UEF .97 efficiency
• Compact design with Quick Flush feature

Cons:

• WiFi control requires a separate Controlr module, which is not included
• No dedicated leak detection feature is listed
• Professional installation is recommended

This model is best viewed as a versatile, efficient upgrade for homes that need installation flexibility. If leak detection is a must-have, you may need to pair this with other home monitoring solutions.

High-Output Pro Option – Noritz EZ Series Pro 11.1 GPM

If you’re comparing tankless water heaters with leak detection features, the Noritz GQ-C3261WX-FF is more of a high-capacity, connected-performance pick than a dedicated leak-monitoring unit. It delivers up to 11.1 GPM, uses Bluetooth connectivity, and is built for indoor or outdoor residential installation with a compact stainless-steel design.

Best For: Larger homes that want very high flow, Bluetooth connectivity, and a durable gas tankless unit.

Pros:

• Up to 11.1 GPM and 199,900 BTU for strong whole-home output
• Bluetooth connectivity for added convenience
• Indoor/outdoor residential installation support
• Stainless steel build with a long heat-exchanger warranty

Cons:

• No dedicated leak detection feature is listed
• Maximum pressure is listed at 60 psi, which may matter in some setups
• Professional installation details are not highlighted in the notes

This is a solid choice when output and connectivity matter more than specialized water-leak sensing. It fits households that need a powerful, durable gas heater with flexible placement options.

Electric Safety-Focused Pick – WINTEMP 18kW WiFi Tankless

For shoppers searching tankless water heaters with leak detection, this WINTEMP electric model leans into safety features more than smart water sensing. It includes leakage protection, overheat protection, and dry-fire protection, plus WiFi control and self-modulating output for a compact electric setup that can serve everyday showers.

Best For: Small to medium homes that want an electric tankless unit with built-in safety protections and WiFi control.

Pros:

• Includes leakage protection, overheat protection, and dry-fire protection
• WiFi control for temperature adjustments
• Self-modulating design helps maintain stable temperature
• Compact wall-mounted form saves space

Cons:

• Requires substantial electrical capacity and correct breaker/wiring setup
• Maximum output is 4.3 GPM, so it’s not a high-demand whole-house option
• Best suited to mild to moderate climate conditions

This is the most safety-oriented option in the group thanks to its explicit leakage protection. It works well for buyers who want electric convenience and a compact footprint, as long as the installation requirements fit the home.

Whole-Home Propane Pick – Rheem RTG 8.4 GPM Indoor LP

If you’re comparing tankless water heaters with leak detection for a large household, this Rheem indoor LP model stands out for whole-home hot water and built-in safety features. Its 8.4 GPM flow rate and 180,000 BTU output are aimed at homes that need multiple fixtures running at once, while the leak detection feature adds an extra layer of peace of mind.

Best For: Large households using liquid propane that want indoor installation, strong multi-fixture performance, and leak detection.

Pros:

• Leak detection plus a multi-point safety system
• 8.4 GPM and 180,000 BTUs support 3-4 simultaneous showers
• Indoor direct-vent design with space-saving wall mount
• Digital LED temperature control with ±1°F adjustments

Cons:

• Professional installation is required
• Liquid propane setup won’t suit natural-gas homes
• Indoor venting adds more installation planning than outdoor units

This is a strong choice if you want a high-capacity propane unit and value the added safety of leak detection. It’s best suited to households that need steady hot water across several points of use rather than a compact point-of-use setup.

Smart Electric Safety Choice – Westinghouse 11kW WiFi Electric

For shoppers looking at tankless water heaters with leak detection in a compact electric format, this Westinghouse 11kW unit is built around safety and convenience. It’s designed for single-point hot water use, heats in about 3 seconds, and includes leak detection as part of its 4-layer protection system.

Best For: Apartments, bathrooms, and single-water-point setups that benefit from smart controls and leak protection.

Pros:

• Leak detection plus 4-layer protection for safer operation
• Heats in 3 seconds with 98% thermal efficiency
• WiFi, Alexa, and Google Home compatibility
• Compact wall-mount design saves floor space

Cons:

• Requires a dedicated 60A double-pole breaker and 8 AWG wire
• Best suited for one water point, not whole-home demand
• Installation setup may be more involved than plug-in alternatives

This model makes sense if you want an electric tankless unit with built-in leak protection and smart features. It’s a practical fit for smaller spaces where quick hot water and easy temperature control matter more than high whole-house flow.

High-Output Outdoor Upgrade – Rheem RTG 9.5 GPM Outdoor WiFi

If you want tankless water heaters with leak detection-style safety in a high-output outdoor format, this Rheem natural gas model is aimed at large households. It delivers 9.5 GPM and 199,900 BTUs for multiple simultaneous showers, with WiFi control and built-in freeze and flame-failure protection.

Best For: Large natural-gas homes that want outdoor installation, strong flow, and app-connected control.

Pros:

• 9.5 GPM and 199,900 BTUs support whole-home use
• Outdoor installation eliminates venting requirements
• WiFi-enabled for connected temperature management
• Built-in freeze protection and flame failure protection

Cons:

• No dedicated leak detection feature is listed in the supplied notes
• Professional installation is required
• Outdoor placement may not suit every home layout

This is the best fit if capacity and simple outdoor installation matter most. While it doesn’t list leak detection specifically, it still offers the kind of protective features and high-output performance buyers often want in a premium tankless setup.

Smart Indoor Propane Pick – Westinghouse 120,000 BTU Indoor Tankless Water Heater

If you want tankless water heaters with leak detection features nearby in a broader buying guide, this Westinghouse unit is really about indoor whole-home hot water with smart control and stable output. It delivers up to 5.1 GPM, supports 2–4 fixtures at once, and uses self-modulating technology to help keep temperature changes to a minimum.

Best For: Indoor propane setups that need whole-home hot water, app control, and consistent temperature stability.

Pros:

• Up to 5.1 GPM and 120,000 BTU for multiple fixtures at once
• Smart WiFi app control plus LED panel for easier temperature monitoring
• ±1°F temperature stability for a steadier shower experience
• CSA-certified with freeze protection and a copper heat exchanger

Cons:

• Propane-powered, so it is not a fit for natural gas homes
• Requires 120V AC power and indoor installation planning
• Leak detection is not listed among its supplied features

This is a strong pick if you prioritize efficient on-demand heating, smart controls, and reliable indoor performance. It is less about advanced leak detection and more about delivering stable hot water with modern convenience.

WiFi LeakGuard Natural Gas Option – Rheem RTG Series 9.5 GPM Natural Gas Tankless Water Heater

Among tankless water heaters with leak detection, this Rheem RTG stands out because it explicitly includes a LeakGuard Leak Detection and Prevention System along with WiFi control. It is built for whole-house natural gas use, delivering up to 9.5 GPM and 199,900 BTU/hr for homes that need reliable hot water across multiple fixtures.

Best For: Large natural gas homes that want WiFi monitoring and built-in leak detection.

Pros:

• LeakGuard leak detection and prevention system included
• WiFi enabled for convenient monitoring and control
• 9.5 GPM supports 3–4 simultaneous showers
• 0.82 UEF and non-condensing design for efficient operation

Cons:

• Indoor installation with direct venting required
• Professional installation is required
• Natural gas only, so it will not suit propane households

If leak detection is a priority, this model is the clearest fit in the group. It combines high output, smart features, and a proven whole-home format for busy households.

High-Efficiency LeakGuard Propane Model – Rheem RTGH Series 9.5 GPM Liquid Propane Tankless Water Heater

If you are comparing tankless water heaters with leak detection and want propane plus top-end efficiency, this Rheem RTGH model is a standout. It combines a 9.5 GPM output with condensing technology, 0.93 UEF efficiency, and built-in EcoNet Wi-Fi with LeakGuard for monitoring and alerts from your smartphone.

Best For: Propane households that want leak detection, WiFi alerts, and very high efficiency.

Pros:

• Built-in EcoNet Wi-Fi and LeakGuard leak detection/prevention
• 0.93 UEF condensing design for high efficiency
• 9.5 GPM and 199,900 BTU for whole-house demand
• Flexible venting and compact design for tighter installs

Cons:

• Indoor installation with direct venting required
• Requires propane fuel service
• Professional installation is implied by the setup complexity

This is the best efficiency-focused pick in the set for propane homes. It adds leak detection and remote monitoring while still delivering the strong output expected from a whole-house tankless system.

How We Picked These Tankless Water Heaters with Leak Detection

We focused on models that balance hot-water output, energy efficiency, and practical safety features. Priority went to units that fit common home setups, offer strong temperature control, and include leak-monitoring or leak-protection capabilities that add an extra layer of confidence.

We also considered fuel type, venting requirements, Wi-Fi or smart-home compatibility, and whether the unit is better suited for indoor or outdoor installation. That combination matters because the best unit on paper is not always the best unit for your plumbing, climate, or household demand.

Quick Comparison: What Matters Most

For larger homes with multiple showers running at once, higher-flow gas models usually make the most sense. Smaller households or point-of-use applications may be better served by electric tankless units, especially where installation simplicity matters more than maximum output.

Also compare BTU rating, gallons per minute, and voltage or gas line requirements. A higher number is not automatically better if your home cannot support the utility demand or if you only need moderate hot water capacity.

Key Buying Factors for Tankless Water Heaters with Leak Detection

Fuel Type and Installation Fit

Natural gas and propane models generally deliver higher flow rates, which helps when several fixtures are used at once. Electric models are often smaller and easier to place, but they typically serve lower-demand households or specific applications.

Flow Rate and Temperature Rise

Look at gallons per minute with your local incoming water temperature in mind. Cold climates reduce usable output, so a heater that seems large enough in mild weather may struggle in winter. Matching capacity to real-world demand is more important than chasing the highest spec.

Leak Detection and Safety Features

Leak detection is most valuable when it can help alert you early or support automatic protection measures. Pair that with features such as freeze protection, overheat safeguards, and strong diagnostics for easier maintenance and fewer surprises.

Controls, Efficiency, and Maintenance

Wi-Fi controls, smart scheduling, and digital temperature settings can make daily use easier. Condensing and high-efficiency designs may cost more upfront, but they can reduce energy use over time. Simple access for service and descaling also matters if you live in a hard-water area.

Who Should Buy Which Tankless Water Heaters with Leak Detection?

Choose a high-output gas model if you need whole-home performance for larger families or multiple bathrooms. Choose an electric unit if you want a compact setup for smaller homes, condos, or locations where gas service is not practical. If your priority is long-term efficiency and advanced controls, look closely at condensing and smart-enabled models. For buyers specifically comparing Tankless Water Heaters with Leak Detection, the best choice is the one that matches your fuel source, household demand, and installation limits without oversizing the system.