Noritz EZTR50 180,000 BTU Tankless Water Heater - HCNAC1177-NG

Noritz EZTR50 180,000 BTU Tankless Water Heater - HCNAC1177-NG

The EZTR50 vents with flexible vent directly through existing B‐Vent with no need to spend time changing existing vent. Water connections are on the top of the heater so now you can use flex lines direct from the top like a tank. 1/2 inch gas line connection to existing line saves time and money.

It is designed to easily convert your 30/40 gallon tank type water heater to tankless technology. This heater can be installed on gas lines as small as 1/2". The EZTR flows up to 6.6 gallons per minute and is Energy Star listed.

Features

• Standard Input‐ Gas consumption ranges from 18,000 BTUh to 180,000 BTUh (EZTR50) and 199,900 BTUh (EZTR75) BTUh
• Capacity Range‐ Flow rates from 9.8 gpm (EZTR50) and 11.1 gpm (EZTR75)
• Compact Design‐ ANSI Z21.10.3/CSA 4.3 certified design for indoor wall‐mounting
• Durable Steel Casing with Polyester Coating
• Venting Options‐ Indoor venting only. N‐Flex Kit (included) is designed for the installation inside of B‐Vent as a sleeve
• Direct Electronic Ignition
• Uniform Energy Factor (UEF) ‐ 0.96(NG) /0.96(LP)
• Temperature Controls‐ Includes built in display that can preset the output temperature to either 100°F to 140°F
• Power Cord Installation Kit‐ 6' power cord is included and attached
• Safety Devices‐ Flame Sensor, Overheat Prevention Device, Lighting Protection Device, Freeze Protection, Condensate Overfill, Fan Rotation Detector
• Additional Features ‐ Temperature Lockout, High Elevation Adjustment

INCLUDED

• EZTR40 | Tankless Water Heater
• Energy Guide
• Installation Manual
• Owners Guide
• Parts List
• Technical Specification
• Complete Installation Kit Accessories

• Lead Free 3/4" Threaded Isolation Valve Kit w/ Male 500K Btuh Pressure Relief Valve (IK-WV-200-1-TH-LF)
• Flex Vent 2" Kit 25 Feet (EZ2FVK-1)
• Flex Vent 2" Conversion Kit (EZ2-CK)
• Aluminum Flex Sleeve

What our Experts Think

• High-output retrofit favorite: 180,000 BTU delivers strong performance for replacing traditional 50-gallon tank systems with minimal modification
• Solid whole-home flow: Up to ~9.8 GPM, supporting multiple showers and fixtures simultaneously in typical family homes
• Designed for easy replacement installs: EZTR platform is engineered specifically for tank-to-tankless conversions, reducing labor and installation complexity
• Energy-efficient operation: Condensing design with very high efficiency (up to ~0.96 UEF depending on setup), helping reduce gas usage over time
• Flexible venting system: Includes flex vent kit for running through existing B-vent, making retrofit projects faster and cleaner
• Top-mounted connections: Simplifies piping transitions and mimics traditional tank layouts for smoother installation
• Compact wall-mounted design: Frees up floor space while still delivering high-capacity performance
• Built-in safety systems: Includes freeze protection, flame monitoring, overheat prevention, and condensate safety controls

Q&A

Q: What is the Noritz EZTR50 tankless water heater?
A: The Noritz EZTR50 is a 180,000 BTU condensing tankless water heater designed specifically as a direct replacement for 40–50 gallon tank water heaters with minimal system modifications.

Q: How much hot water can it provide?
A: It delivers up to 9.8 GPM, allowing multiple fixtures such as showers and sinks to run simultaneously in a typical residential setting.

Q: What fuel type does it use?
A: The HCNAC1177-NG model operates on natural gas (NG) for high-efficiency residential water heating.

Q: Is the EZTR50 energy efficient?
A: Yes, it features high-efficiency condensing technology with a UEF around 0.96, reducing energy waste by heating water only when needed.

Q: Where is it installed?
A: It is designed for indoor installation with flexible venting through existing B-vent systems, making retrofit installation easier.

Q: Is it suitable for replacing a traditional tank heater?
A: Yes, it is specifically engineered for tank-to-tankless conversions, allowing homeowners to upgrade without major plumbing changes.

Q: What type of homes is it best for?
A: It is ideal for medium-sized households (typically 2–4 bathrooms) needing consistent hot water for daily use.

Q: Why choose a tankless system like the EZTR50?
A: It provides continuous hot water on demand, space-saving wall mounting, and improved efficiency compared to traditional storage tank heaters, making it a strong retrofit solution

Maintenance Tips

• Annual descaling (critical): Flush heat exchanger to prevent scale buildup and maintain up to ~9.8 GPM flow and efficiency (~0.96 UEF).
• Clean inlet water filter: Rinse every 6–12 months to maintain strong flow and prevent ignition or temperature issues.
• Check flex vent system (included): Inspect 25 ft flex vent for sagging, leaks, or blockage to ensure proper exhaust through existing B-vent.
• Inspect isolation valve kit: Test valves periodically so service/draining can be done easily and safely.
• Monitor condensate drain: Keep drain line clear to prevent backup or shutdown errors (condensing operation).
• Check gas connection & pressure: Ensure stable 1/2" gas line supply is within spec for full 180,000 BTU demand.
• Keep unit exterior clean: Remove dust, insects, and debris for proper airflow and long-term reliability.
• Test safety systems yearly: Includes freeze protection, flame sensor, overheat protection, and fan operation.
• Professional service every 1–2 years: Recommended for burner inspection, heat exchanger cleaning, and vent safety checks.