Noritz 9.8 GPM 180,000 BTU Residential Natural Gas EZTR 50 Gallon Tank Replacement Condensing Tankless Water Heater (.98 UEF)

The Noritz EZTR50-NG EZTR Series 9.8 GPM 180,000 BTU Residential Natural Gas Condensing Tankless Water Heater is specifically engineered to simplify the replacement of traditional 50-gallon tank water heaters while delivering an endless supply of hot water. Featuring an ultra-high 0.98 UEF Energy Star® certified condensing design, the EZTR50-NG heats water only when it is needed, helping reduce energy consumption and eliminate the standby heat loss associated with conventional storage tank water heaters.

Designed with an innovative top-mount water connection layout, the EZTR Series helps streamline retrofit installations by aligning with many existing tank water heater plumbing configurations. With a powerful 180,000 BTU input and up to 9.8 GPM of hot water delivery, and flexible indoor or outdoor installation options, the EZTR50-NG provides reliable hot water for homes with multiple simultaneous showers, appliances, and fixtures while maximizing energy efficiency and long-term performance.

Product Features:

• 180,000 BTU Input: Delivers powerful natural gas heating capacity for continuous, on-demand hot water.
• Up to 9.8 GPM Flow Rate: Provides hot water for multiple bathrooms, appliances, and fixtures simultaneously, depending on incoming water temperature and household demand.
• 0.98 UEF Condensing Efficiency: High-efficiency condensing technology captures additional heat from combustion to reduce energy waste and lower operating costs.
• Designed to Replace 50-Gallon Tank Water Heaters: Top-mounted water connections and a space-saving cabinet help simplify replacement of many traditional 50-gallon storage tank water heaters.
• Compact Wall-Mounted Design: Frees up valuable floor space compared to conventional tank water heaters while providing unlimited hot water.
• Flexible PVC Venting: Compatible with approved PVC, CPVC, and polypropylene venting options for greater installation flexibility.
• Wi-Fi Capable: Compatible with the optional Noritz Connect™ adapter for remote monitoring and control.
• Energy Star® Certified: Meets high-efficiency performance standards to help reduce utility costs while maintaining dependable hot water delivery.

What Is an Isolation Valve Kit?

An isolation valve kit is an important accessory used during tankless water heater installation. These valves connect to the hot and cold water lines and allow the water heater to be shut off, serviced, flushed, or descaled without turning off water to the entire home.

Isolation valves are especially important for tankless water heaters because routine maintenance helps preserve efficiency and extend the life of the heat exchanger. In areas with hard water, mineral scale can accumulate inside the unit over time. Isolation valves make periodic flushing and descaling much faster and more convenient.

Short vs. Long Isolation Valve Kit

For this Noritz EZTR50-NG tankless water heater, you only need to select one isolation valve kit based on your installation requirements.

• IK-WV-200-5-TH-S Short Isolation Valve Kit: Ideal for installations where space is limited or a more compact plumbing connection is preferred.
• IK-WV-200-5-TH-L Long Isolation Valve Kit: Recommended when additional clearance or easier access for future servicing is desired.

Both valve kits include 3/4" threaded isolation valves and a lead-free pressure relief valve. The best choice depends on your available installation space, plumbing layout, and service accessibility preferences.

Understanding Tankless Water Heater Sizing

Unlike traditional storage tank water heaters, tankless water heaters are sized based on flow rate (GPM) and temperature rise rather than tank capacity. Flow rate measures how much hot water the unit can produce each minute, while temperature rise represents the difference between the incoming groundwater temperature and your desired hot water temperature.

Always size a tankless water heater using your winter groundwater temperature, since colder incoming water requires more heating. As the required temperature rise increases, the available hot water flow rate decreases.

For example, if your desired hot water temperature is 120°F and your winter groundwater temperature is 55°F, the required temperature rise is:

120°F - 55°F = 65°F Temperature Rise

Use the Flow Rate Chart shown in the product images to determine how much hot water the EZTR50-NG can produce at your required temperature rise. This helps ensure the unit is properly sized for your home's showers, sinks, dishwashers, washing machines, and other hot water demands.

Warranty

This product includes a manufacturer's limited residential warranty, including up to 25 years on the heat exchanger, 5 years on parts, and 1 year reasonable labor coverage for qualifying residential installations. Always verify fuel type, venting requirements, electrical requirements, water quality, installation clearances, required accessories, and local plumbing and mechanical codes before installation.