Best Tankless Water Heater Models by Type (2025 Buyer’s Guide)

Searching for the best tankless water heater? Whether you're upgrading your home's water system or building new, choosing the right model is key. This guide breaks down the top-performing tankless water heater models in 2025 by type: electric, gas, indoor, and outdoor—so you can confidently invest in comfort, performance, and energy efficiency.

⚡ Best Electric Tankless Water Heater Models

⭐ 1. Stiebel Eltron Tempra Plus 24 kW

• Efficiency: Advanced flow control and self-modulation

• Features: Digital display, sleek German design, very quiet

• Flow Rate: Up to 5.0 GPM

• Ideal For: 2–3 bathroom homes

• 💰 Price: ~$800

• Why We Love It: One of the most reliable and consistent electric models on the market.

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⭐ 2. EcoSmart ECO 27

• Efficiency: Self-modulating, adjusts energy use to demand

• Features: Compact, wall-mounted design

• Flow Rate: Up to 6.5 GPM (in warm climates)

• Ideal For: Small homes or single-use points

• 💰 Price: ~$500

• Why We Love It: Budget-friendly and energy efficient with strong user reviews.

  
  

🔥 Best Gas Tankless Water Heater Models

⭐ 1. Rinnai RU160iN (Indoor, Natural Gas)

• Efficiency: ENERGY STAR® certified, condensing model

• Features: Wi-Fi compatibility, compact size

• Flow Rate: Up to 7 GPM

• Ideal For: Mid-size to large homes

• 💰 Price: ~$1,300

• Why We Love It: Excellent efficiency, reliability, and smart features.

⭐ 2. Takagi T-H3-DV-N

• Efficiency: Ultra-low NOx emissions, condensing

• Features: Durable commercial-grade design

• Flow Rate: Up to 10 GPM

• Ideal For: Large families or simultaneous use in multiple locations

• 💰 Price: ~$1,500

• Why We Love It: High-performance and built to last.

  
  

  

  
  

🏠 Best Indoor Tankless Water Heater Models

⭐ 1. Navien NPE-240A2

• Efficiency: 0.97 UEF (ultra-efficient), ENERGY STAR® rated

• Features: Built-in recirculation pump, Wi-Fi control

• Flow Rate: Up to 11.2 GPM

• Ideal For: Large households in cold climates

• 💰 Price: ~$1,900

• Why We Love It: Feature-rich with outstanding performance.

  
  

⭐ 2. Noritz NRC66DVNG

• Efficiency: Condensing, energy-saving

• Features: Digital temperature control, indoor direct vent

• Flow Rate: 6.6 GPM

• Ideal For: Smaller homes or condos

• 💰 Price: ~$1,000

• Why We Love It: Great value and compact size.

  
  

🌦️ Best Outdoor Tankless Water Heater Models

⭐ 1. Rinnai V65eN

• Efficiency: Non-condensing, ENERGY STAR®

• Features: Weather-resistant exterior, no venting needed

• Flow Rate: 6.5 GPM

• Ideal For: Homes in warmer climates

• 💰 Price: ~$950

• Why We Love It: Great for space-saving outdoor installs.

  
  

⭐ 2. Takagi T-KJr2-OS-NG

• Efficiency: Non-condensing, built for outdoor use

• Features: Freeze protection, simple maintenance

• Flow Rate: 6.6 GPM

• Ideal For: Vacation homes or mild-weather areas

• 💰 Price: ~$900

• Why We Love It: Affordable and reliable in warm regions.

  
  

Choosing the Right Model: Quick Tips

Type	Best For	Price Range	Install Difficulty
Electric	Small homes, point-of-use	$450–$800	Easy
Gas	Medium to large homes	$1,000–$1,500	Moderate
Indoor	Cold climates	$1,000–$2,000	Medium
Outdoor	Warm climates	$850–$1,200	Easy

📌 So, Do You Need a Permit in San Jose?

Yes, you do. In the City of San Jose, replacing a tankless water heater requires a permit—whether it’s a like-for-like swap or a full system upgrade.

Permits help ensure your installation is:

• ✔️ Safe and compliant with California Plumbing and Mechanical Codes

• ✔️ Properly connected to gas, electric, and water lines

• ✔️ Installed to pass inspection and avoid future legal or safety issues

  
  

What Kind of Permits Are Required?

Depending on your setup, one or more of the following permits may be needed:

• Plumbing Permit: Always required for replacing a water heater

• Mechanical Permit: Needed if venting is added or modified

• Electrical Permit: Required if you're updating wiring or installing a hybrid/electric model

Pro tip: The City may also require an inspection to verify code compliance—this is often a simple process but very important for safety and legal documentation.

Why Are Permits So Important for Tankless Units?

Tankless water heaters are more complex than traditional tank models. Their installation typically involves:

• ✅ Gas line upgrades to handle higher BTU demands

• ✅ Ventilation adjustments for safe exhaust (especially with indoor units)

• ✅ Electrical upgrades for units with digital or hybrid features

Skipping the permit process could result in:

• 🚫 Safety risks like gas leaks or carbon monoxide exposure

• 🚫 Problems with home insurance claims

• 🚫 Delays or extra costs during future home sales or inspections

Tankless Water Heater Installation Service

Don’t Take the Risk—Do It Right the First Time

Working with a licensed plumber or contractor ensures your new tankless water heater is:

• Installed safely

• Up to code

• Covered by warranty and insurance

Need Help Chooding or Installing?

Whether you need help choosing the right tankless water heater or want professional installation in your area, our certified team at Local Rooter Corp. is here to help.

✅ Free sizing consultation

✅ Licensed installation

✅ Permits & code compliance

✅ Energy-efficient options

📞 Call: (408) 868 8759

🌐 Visit: www.localrooter.net

📍 Serving homeowners in San Jose and surrounding areas