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FOUNTAIN VALLEY, CALIFORNIAAs a leader in the water heater industry, Noritz America’s innovative approach to energy savings and superior hot-water delivery intentionally puts the consumer and professional at the forefront. Down to the installation itself, Noritz works to keep the installer one step ahead by offering an updated checklist to avoid poor installs.

Using a backwards navigation technique, Noritz identified common post-installation issues, collected from their professional network, to create and update the checklist. The goal: To make certain plumbers and HVAC technicians address key areas of installation.

The checklist provides the installer with a series of yes-and-no items to ensure a successful installation. If at any point a line item requires a “no,” the installer can remedy the issue to avoid malfunction.

Let’s explore the three most common issues that arise, post-installation, to represent the overall installation checklist.

  1. Location

Whether indoors in the same location as the old storage tank it is replacing or outdoors in warmer climates, your installation location can affect unit performance. Know your clearances to allow for proper venting and be aware of the unit’s placement to avoid external blockages that could take up airspace.

Suppose the unit is placed in an area not openly visible to the homeowner. In that case, potential leakage may not be found immediately, causing further damage.

Using undersized gas lines at great distances with your unit can also impact system performance. Although a half-inch gas line will result in the proper BTU inputs for various gas appliances in a home, gas pressure problems may arise if any two or more of these appliances fire simultaneously. To avoid this issue, install a larger gas line (3/4-inch), or run a dedicated half-inch line to the tankless water heater.

In addition, how far away your tankless unit is located from outlets throughout the house will inevitably impact efficient hot-water delivery. The longer the pipe run, the more time it will take for water at the desired temperature to arrive.

Water within the tankless unit will rise to the desired temperature within 15 seconds, notes Noritz Application Engineering and Service Training Supervisor Eric Manzano. “Everything else is just travel time between the water heater and fixture location.”

By definition, tankless water heaters deliver hot water at the correct temperature on demand. But a dedicated recirculation line with a recirculation pump attached to or built into the unit can quickly move the hot water to the desired location.

Condensation is another important issue. If a tankless unit is installed below ground level (so that gravity cannot drive drainage), a condensation pump can move condensation away from the unit.

Remember too: Condensation is acidic. Plan carefully where the condensate pipe run will terminate to avoid condensation eating through the home’s plumbing system or affecting natural environments, such as gardens or flower beds. Utilize PVC plastic tubing to drain the pump.

On outdoor installations, locate the heater away from operable doors and windows. If your locale experiences snow, sleet or hail to any extent, you are better off installing indoors. Outdoor systems can perform only to -4° Fahrenheit; indoor units are rated down to -30°F.

Even indoors, you can still have cold-weather issues: The interior workings of indoor tankless water heaters are at risk of cold air infiltrating their venting, especially if you have a short vent run to the outdoors. Run a longer vent, so that the frigid air is not hitting the heat exchanger.

  1. Water Quality

Soft water has a different texture than hard water. This is due to minerals being stripped from the water in the softening process. In contrast, hard water can cause damage to your unit and pipes. To avoid issues, use a water softener or a variety of water treatments, such as H2Flow, to treat the water to meet specifications.

Noritz recently released an updated version of Scale Shield, which offers an alternative to softening. Scale Shield prevents the buildup of hard water minerals from sticking to the pipes by turning the pipes into slick walls that prevent limescale from attaching in the water heater pipes.

Scale Shield uses a polyphosphate material to sequestrate the calcium before it enters the heater. Installed in the water heater’s water supply line, Scale Shield renders the calcium harmless, sending it down a household drain.

You or your homeowner customer should perform a descaling procedure at least once a year on well water or commercial applications, or once every two years for municipal treated water, depending on the hardness of the water. Descaling allows you to gauge if there is scale buildup within the unit. If scale is identified, you can then determine if your treatments are effective or need to be adjusted.

  1. Gas Supply

Tankless water heaters are commonly used in retrofit applications, with contractors working with existing gas supply systems. Unfortunately, gas meters are often undersized: While tankless water heaters have inputs of around 200,000 BTUs per hour, gas meters sit at 120,000 to 150,000 BTUs. Obviously, this handicaps the unit’s capabilities.

The gas meter must be sized properly to support multiple, simultaneous applications, such as a bathroom shower and a gas stove. Gas companies can change out meters, allowing the water heater to perform at full capacity when household demand requires it.

Additional Key Areas

  • Venting the water heater:

Venting exits through the roof or the sidewall and can and is installed with a Category III stainless steel pipe for non-condensing units. Use PVC, CPVC, or polypropylene for condensing units to ensure the exhaust is away from operable doors and windows.

  • Dip switch setting errors

Often when a dip switch is forgotten during installation, an Error Code 90 can appear. This indicates combustion abnormality or system obstruction. The dip switches affect the fan motors, which operate at different speeds based on demand (gallons per minute, or gpm) and installation conditions. Although issues may not arise until further down the line, remember to set the dip switches according to the specifications in the instruction manual to avoid malfunctions.

  • Trial Operation

During your trial operation, take note of normal sounds, such as clicking upon ignition and a whooshing sound during combustion as the water heater fires up. Humming noises from the water control valve ensure proper mix ratio of hot and cold water to achieve the desired temperature.  During the shutdown, the fan may run slightly longer than the unit to expel exhaust that may be venting.

Invaluable Tool

Noritz product experts recommend reading the installation manual, including the checklist, before installing. That way, you will more likely avoid mishaps and confirm that the correct unit has been chosen, allowing you to proactively plan the installation.

“The installation checklist is the best tool for installers to make sure they covered all their bases,” says Manzano. “It’s a vital component in a successful installation.”

Available online, the checklist is also included with the product purchase. In addition, the Pro Card app gives full access to installation manuals, product manuals and information, dip switch settings, gas pipe settings, and more.

Noritz technical support is available for any questions or concerns at 866-766-7489. For more information on the installation checklist, listen to the Noritz “Talking Tankless” podcast, Episode 7.