Noritz 8.3 GPM 180,000 BTU Residential Natural Gas Direct Vent Concentric Tankless Water Heater (.82 UEF)

The Noritz NR83-DVC-NG 8.3 GPM 180,000 BTU Residential Natural Gas Direct Vent Concentric Tankless Water Heater delivers an endless supply of hot water while helping reduce energy consumption by heating water only when it's needed. Unlike traditional storage tank water heaters that continuously maintain a reservoir of heated water, the NR83-DVC-NG provides continuous on-demand hot water without standby energy loss, making it an excellent choice for larger homes with multiple bathrooms and higher simultaneous hot water demands.

Designed for indoor installation, the NR83-DVC-NG features a direct vent concentric system that draws combustion air from outside while safely exhausting combustion gases through a single 5-inch/3-inch Noritz stainless steel concentric vent. Delivering up to 180,000 BTU of natural gas heating power and a maximum flow rate of 8.3 gallons per minute, this compact wall-mounted tankless water heater combines high-performance operation, advanced safety features, and durable commercial-grade components for years of dependable residential hot water service.

Product Features:

• 180,000 BTU Maximum Input: Provides powerful natural gas heating capacity for larger residential hot water applications.
• Up to 8.3 GPM Flow Rate: Delivers continuous hot water to multiple showers, faucets, dishwashers, and washing machines simultaneously, depending on incoming water temperature and household demand.
• Direct Vent Concentric Installation: Designed for indoor installation using an approved 5-inch/3-inch Noritz stainless steel concentric vent system that combines combustion air intake and exhaust into a single vent assembly.
• Non-Condensing Design: Delivers dependable performance with a Uniform Energy Factor (UEF) of 0.82 while heating water only when needed.
• Commercial-Grade Copper Heat Exchanger: Manufactured with commercial-grade copper tubing approximately 25% thicker than standard residential models to provide enhanced durability and long-term reliability.
• Fully Modulating Burner: Automatically adjusts between approximately 18,000 and 180,000 BTU to maintain consistent outlet water temperatures while improving energy efficiency.
• Adjustable Temperature Settings: Includes a built-in remote thermostat with adjustable temperature settings from 115°F to 140°F, allowing precise control for residential hot water applications.
• Quick Connect Compatible: Two identical NR83 units can be connected using the optional Noritz Quick Connect Cord to nearly double hot water capacity without requiring an additional controller.
• Scale Detection Reminder: Built-in service reminder alerts homeowners when routine maintenance and descaling should be performed to help maintain peak efficiency.
• Built-In Freeze Protection: Helps protect the heat exchanger in temperatures down to -30°F when installed according to manufacturer requirements and connected to electrical power.
• Advanced Safety Features: Includes flame sensing, overheat prevention, fan rotation monitoring, thermal fuse, lightning protection, temperature lockout, high elevation adjustment, and advanced self-diagnostic monitoring.

What Is an Isolation Valve Kit?

An isolation valve kit is a recommended accessory for every tankless water heater installation. Isolation valves connect to the hot and cold water lines and allow the water heater to be isolated for flushing, descaling, maintenance, or servicing without shutting off water to the rest of the home.

Routine flushing removes mineral deposits that naturally accumulate inside the heat exchanger, especially in areas with hard water. Installing isolation valves makes annual maintenance significantly easier while helping preserve efficiency, maintain reliable performance, and extend the life of the water heater.

Short vs. Long Isolation Valve Kit

For the Noritz NR83-DVC-NG, only one isolation valve kit is required depending on your installation layout.

• IK-WV-200-5-TH-S Short Isolation Valve Kit: Recommended for installations where limited space requires a compact plumbing configuration.
• IK-WV-200-5-TH-L Long Isolation Valve Kit: Ideal when additional clearance is available, allowing easier future maintenance and servicing.

Both isolation valve kits include durable 3/4-inch threaded hot and cold isolation valves together with a lead-free pressure relief valve. The correct kit depends on the available installation space and plumbing layout.

Understanding Tankless Water Heater Sizing

Unlike traditional storage tank water heaters, tankless water heaters are sized using flow rate (GPM) and temperature rise rather than storage capacity. Flow rate represents the amount of hot water the unit can produce each minute, while temperature rise is the difference between the incoming groundwater temperature and your desired outlet temperature.

Always size a tankless water heater using your area's winter groundwater temperature, since colder incoming water requires more heating capacity and reduces the maximum available flow rate.

For example, if your desired hot water temperature is 120°F and the incoming groundwater temperature is 50°F, the required temperature rise is:

120°F − 50°F = 70°F Temperature Rise

Use the Noritz flow rate chart included with the product literature to determine the expected hot water output at your required temperature rise. This helps ensure the water heater is properly sized for your household's peak simultaneous hot water demand.

Warranty

The NR83-DVC-NG includes Noritz's residential limited warranty featuring a 12-year heat exchanger warranty for standard residential installations, a 5-year parts warranty, and a 1-year reasonable labor warranty. When installed with a controlled recirculation system using a minimum aquastat pump control, the heat exchanger warranty remains 12 years or 6,500 operational hours, whichever occurs first. Always verify natural gas supply, approved concentric venting requirements, electrical requirements, water quality, local plumbing and mechanical codes, and all required accessories prior to installation.