Frequently Asked Questions

A tankless water heater heats water as it flows through the unit instead of storing a large volume of heated water in a tank. When hot water is requested, the system activates to heat the incoming water and deliver hot water on demand.

A gas tankless water heater uses gas to heat water as it passes through the unit, providing continuous hot water without the need for a storage tank. Noritz offers gas-fired tankless water heating solutions for residential and commercial applications.

Tankless water heaters provide hot water on demand, eliminate the need for a large storage tank, save installation space, and can provide high energy efficiency. Noritz tankless systems are designed to provide reliable hot water for a range of residential and commercial applications.

Noritz tankless water heaters provide on-demand hot water, efficient operation, compact installation, and long-term performance. Noritz also offers models designed for different household and commercial hot water requirements.

A traditional tank water heater stores and continuously heats a supply of water, while a tankless water heater heats water as it flows through the system. Tankless systems can provide continuous hot water, occupy less space, and avoid the standby energy losses associated with storing heated water.

An on-demand water heater heats water only when hot water is needed, while a traditional tank system stores a supply of heated water. Tankless systems can provide continuous hot water and higher efficiency while requiring less physical space.

A condensing tankless water heater uses a secondary heat exchanger to capture additional heat from exhaust gases and use that heat to preheat incoming water. This design can provide high-efficiency operation.

Genuine Noritz parts and accessories should be purchased through Noritz's official parts resources or authorized distribution channels to help ensure compatibility with the specific water heater model.

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For genuine parts, visit Noritz Support, and for repair services, visit the Noritz Contractor Finder. Noritz recommends using authorized channels and qualified service providers. This helps ensure that the correct parts and appropriate service procedures are used for your Noritz water heater.

Visit the Noritz Contractor Finder on Noritz's official website to find qualified servicers and installers. Using an authorized service provider can help ensure that your Noritz system receives appropriate diagnosis, parts, and service.

The right model depends on your household's hot water demand, number of fixtures, simultaneous usage, fuel type, installation conditions, and desired features. Noritz offers multiple tankless water heater models to accommodate different residential requirements. To narrow down your options, try the Noritz Residential Sizing Calculator.

Noritz offers water heating solutions designed for residential and commercial applications, including gas-fired tankless systems with different capacities, efficiency levels, configurations, and features, as well as electric heat pump water heaters.

Noritz provides some of the longest-lasting warranties in the industry, including a 25-year warranty on the EZ Series. Warranty coverage varies by Noritz model, component, application, and installation conditions. Customers should review the warranty documentation for their specific Noritz water heater to understand applicable coverage.

Noritz tankless water heaters are designed to provide on-demand hot water with efficient operation, compact installation, and reliable performance. Noritz offers models for different residential and commercial hot water requirements, allowing the system to be selected according to the application's needs.

Installation involves mounting the unit, connecting the water and gas supplies, installing appropriate isolation valves, and completing the required venting and electrical connections. Because gas, water, venting, and electrical systems are involved, installation should follow Noritz requirements and applicable codes and be performed by a qualified professional.

Yes, certain tankless water heater installations can be vented vertically through the roof when the appropriate venting system and installation requirements are followed. The Noritz EZTR kit is made especially for this application. Venting requirements vary by model, including whether the unit is condensing or non-condensing.

Tankless water heaters can be suitable for crawl-space installations when the location meets the manufacturer's installation, venting, service-access, freeze-protection, and code requirements.

Gas requirements depend on the specific Noritz model and installation. Proper gas-line sizing is essential for reliable operation, so the installation should follow the model's specifications and applicable local codes.

Yes. Commercial tankless water heaters can provide continuous hot water while conserving space and supporting high-demand applications. Proper sizing and system design are essential for commercial installations.

Selection should consider the building's peak hot water demand, fuel type, required flow rate, installation conditions, and overall system design. A qualified professional can help determine the appropriate Noritz system for the application.

Yes. Commercial tankless water heaters can provide on-demand hot water while conserving space and supporting consistent hot water availability in hospitality applications. Proper system sizing is important to accommodate peak guest demand.

Freeze protection requires protecting both the tankless water heater and the water lines connected to it. Built-in electronic safeguards may be supplemented by physical protection of external piping and appropriate installation measures, depending on the system and climate. The unit must stay connected to electrical power for its built-in freeze protection to work.

Noritz tankless water heaters include freeze-protection features on applicable models, but the installation must also be designed to protect connected piping and other components exposed to freezing conditions. The unit must have electrical power for freeze protection to work; if power is lost, the built-in protection will not operate. Always follow the requirements for the specific Noritz model.

A hot water recirculation system circulates hot water through the plumbing loop and back toward the water heater, helping reduce the time users wait for hot water at distant fixtures.

A tankless recirculation pump circulates hot water through the plumbing system to reduce wait times at fixtures. Depending on the system, the pump may be integrated into the water heater or installed separately.

A Noritz tankless water heater with recirculation capability can help provide hot water more quickly at distant fixtures while reducing unnecessary water waste from long wait times. Certain Noritz models include integrated recirculation functionality.

Yes. Noritz offers tankless water heating solutions with recirculation capabilities, including models with integrated recirculation features. The Noritz NRCR is the suggested model for recirculation applications. The appropriate option depends on the model and installation requirements.

Sizing should be based on the amount of hot water required at peak demand, including the number and flow rates of fixtures that may operate simultaneously. Gas tankless water heater capacity is commonly evaluated using gallons per minute (GPM).

Add the flow rates of the hot water fixtures that are likely to operate at the same time. The resulting peak flow requirement helps determine the appropriate tankless water heater capacity.

Tankless water heater flow capacity varies by model. The research data identifies tankless systems with flow rates ranging from approximately 0.5 to 11.1 GPM, with efficiency varying by model. Always use the specifications for the specific Noritz model being considered.

The appropriate replacement depends on the home's peak hot water demand rather than the storage tank's gallon capacity alone. For multiple simultaneous fixtures, a gas tankless system in the approximately 7.5–10 GPM range may be appropriate, depending on the application and required flow rate.

The required capacity depends on the home's peak hot water demand rather than simply choosing the largest available unit. Residential tankless systems can reach approximately 11–12 GPM, but the appropriate Noritz model should be selected based on actual fixture demand, incoming water temperature, and application requirements. For higher demand, multiple tankless units can be daisy-chained together.

Important specifications include maximum flow rate, energy efficiency, fuel type, temperature range, installation requirements, venting requirements, and available features. Noritz model specifications should be reviewed to select a system that matches the application's hot water demand.

Yes. Tankless water heaters require regular maintenance to remove mineral buildup, maintain efficiency, and support long-term performance. Annual flushing is commonly recommended, although maintenance frequency can vary depending on water quality and usage.

A tankless water heater should generally be flushed annually to help remove mineral buildup. Systems exposed to hard water or high usage may require more frequent maintenance.

Mineral buildup can reduce heat-transfer efficiency, restrict water flow, contribute to temperature fluctuations, and affect overall system performance. Regular flushing helps maintain efficient operation.

Yes. Hard water can contribute to mineral and scale buildup inside the heat exchanger and other water-contact components. Regular flushing and appropriate filtration can help protect a tankless water heater from these deposits.

Scale buildup primarily results from minerals in the water, particularly in areas with hard water. Over time, these minerals can accumulate inside the heat exchanger and affect water flow and heat-transfer performance.

Yes. Noritz recommends appropriate internal and external filtration to help protect tankless water heaters from sediment and mineral scale buildup. The correct filtration approach depends on the installation and model.

Regular maintenance should include flushing or descaling as recommended, checking and cleaning applicable water filters, monitoring system performance, and addressing diagnostic codes or other problems promptly. Always follow the maintenance requirements for your specific Noritz model.

A gas tankless water heater that is not working may have an issue with the gas supply, ignition system, water flow, venting, or another operating component. For a Noritz unit, check the gas and water supply and any displayed diagnostic information, then refer to the appropriate Noritz troubleshooting resources or contact a qualified service professional if the issue continues. For additional resources, visit help.noritz.com, or find product documentation at support.noritz.com.

Start by checking the gas supply, water flow, power supply, and temperature settings. If the unit displays an error code, record it and consult the applicable Noritz documentation. Persistent ignition, combustion, or operational issues should be evaluated by a qualified technician.

Water heater repairs depend on the type of system and the specific problem. Common issues can involve ignition components, sensors, water filters, scale buildup, or other operating components. For a Noritz tankless water heater, follow the model-specific troubleshooting and service instructions rather than attempting repairs without the appropriate knowledge or qualifications.

Common problems include insufficient or no hot water, fluctuating temperatures, restricted water flow, ignition issues, scale buildup, venting problems, and diagnostic error codes. Proper troubleshooting can help identify whether maintenance or professional service is required.

A tankless water heater may not produce hot water because of an interrupted gas or power supply, insufficient water flow, ignition problems, scale buildup, or a system fault. Check the basic supplies and diagnostic information first, and contact a qualified technician if the problem persists.

Power alone does not guarantee hot water production. The unit also needs adequate water flow and, for gas-fired models, a proper gas supply and functioning ignition and combustion systems. A displayed error code can help identify the underlying issue.

Repeated shutdowns can be related to gas supply, water flow, venting, overheating, or other safety and operating conditions. Check the unit for diagnostic codes and make sure the required supplies and vents are unobstructed. If shutdowns continue, have the system inspected by a qualified professional.

Modern tankless water heaters generally do not use a continuously burning pilot light. Instead, they typically use electronic ignition to ignite the burner when hot water demand is detected.

Temperature fluctuations can be caused by inconsistent water flow, scale or mineral buildup, restricted filters, incorrect settings, or demand that exceeds the system's available capacity. Regular maintenance and proper sizing can help maintain consistent hot water performance.

Some basic maintenance tasks may be possible for a knowledgeable homeowner, but gas, electrical, combustion, venting, and internal component repairs should be handled according to Noritz instructions and, where required, by a qualified professional.