If the pressure being supplied into the water heater is low, the pressure coming out of the water heater will also be low. If the supply pressure is normal and the water pressure is still low, the water heater may be too small for the application.

This may be a failure of the relief valve, or a response to dangerously high temperatures or pressures in the water heater.

A condensing heater passes hot flue gases through a secondary, stainless steel heat exchanger to preheat the inlet water temperature.  The exhaust gas is cooled and steam in the exhaust gas condenses on the vent surface.  A condensing tankless heater is more efficient because of this pre-heating process.  Our condensing heater is 93% efficient as compared to 80% efficiency for most non-condensing tankless heaters.  This saves you about 10-15% more on your water heating bill.

A Noritz water heater cannot be used as a pool heater due to the chemicals that can be harmful to the copper components within the unit.  Although a pool heater might be necessary in order to heat up the pool quickly, a secondary heat exchanger specifically for pool applications (made of Titanium, Stainless Steel or Cupro-Nickel) can be used with a Noritz unit to gradually raise the temperature of the pool water. 

The hot water from the water heater will indirectly heat the ambient pool water while they are both flowing through the heat exchanger through the connections provided.  More information can be found at http://www.heatexchangersonline.com/poolheaters.htm regarding specific models and capabilities.

Yes, you can use the Noritz tankless water heaters for domestic hot water in conjunction with a heating system but not solely for a heating system. Use an NH series boiler for closed-loop heating applications.

Yes. It is best that the preheat system has a mixing valve to eliminate temperature fluctuation and insure that the water going into the Noritz heater does not exceed 110°F.

If the heater is not turning on, but there is a display on the remote, the filter might be clogged. Debris in the pipes from installation can clog the filter. Another possibility is reversed water connections: cold water supply connected to the hot water outlet, hot water supply line connected to cold water inlet.

If there is nothing on the display, verify that the heater is plugged in, the remote is plugged in (no damage to the wire), the outlet is receiving power, and the circuit breaker has not tripped.

Every Noritz tankless water heater has a minimum flow requirement which must be detected in order to activate the heater. If your water heater shuts off during usage, check to see if your filter is clean. Verify that gas, water, and power are supplied to the heater as well. . Also be aware that in residential situations, higher set temperatures may cause you to use less hot water as you mix your cold and hot supply to comfortable temperatures. If your set temperature is above 120°F, try lowering the set temperature of the water heater to ensure that you are meeting the minimum flow requirement of the water heater while tempering.

Long pipe runs are the most common cause of long wait times.  If that is not the case have the installer check for other plumbing problems.

The heater has control valves that will make a “beeping” sound. This can be triggered during normal operation or as part of a self diagnostic mode of the heater even during standby mode. If you are hearing other sounds please call Technical Service at 866-766-7489, option 3 to verify that the heater is working properly.

This can be a result of a blockage in the flue, incorrect vent sizing, incorrect vent length, and/or incorrect gas pressure/gas type. If all of these match the requirements in the installation manual and there is still a rumbling sound, please call Technical Service at 866-766-7489, option 3.

This could be an issue with the water pressure coming to the heater or a plumbing issue such as cross piping. A licensed plumber can help identify this issue.

This could be that the incorrect size tankless unit was installed for your application. Tankless water heaters are installed based upon the peak demand in an application.

If a portion of your fixtures are receiving hot water, but not all, your plumbing may be preventing hot water from reaching those fixtures. Please consult a plumber or Technical Service at 866-766-7489, option 3.

On the new stainless steel models, the rating plates are located on the side of the heater instead of the front.  A larger clearance was required by CSA in order to read the rating plate.

This information is normally located with the rating sticker on the front cover of unit.  On stainless steel model heaters the information can be found on the side of the case.

The clearances are listed on the N-Vent pipe material as well as in the installation manual for the heater.

At least one foot of clearance is recommended for servicing purposes.

It is not required, but can be beneficial if you are in an area which incurs frequent power outages. The battery back-up must produce a pure sine wave.  Examples of such models include the APC (American Power Conversion Corporation) Smart UPS 750VA and above, Powerware 5115 (500 VA or above), Tripp Lite SU1000XL, Cyberpower PR1500, Belkin F6C100, and MGE Pulsar EX700RT.

Noritz recommends at least ¾” gas line for our products.  For help with specific sizing, consult with a licensed plumber to determine exact size needed.

Tankless water heaters require more BTU demand than regular storage tanks therefore it is recommended that you contact a qualified plumber to see if your gas line needs to be changed.

Please refer to the table below for available field conversion kits.  If there is no field conversion kit available, the conversion must be performed at Noritz.  For further detail contact Noritz Technical Service at 866-766-7489, option 3.

Noritz is the #1 manufacturer of tankless water heaters worldwide and has been in the industry for over 50 years. Customers trust Noritz because due to our superior comfort, quality, and support. Advances in our heat exchanger and burner technologies have increased efficiency and temperature control, ensuring comfort for our customers. Product durability is also enhanced with new heat exchangers that use 25% thicker copper piping than the industry standard. Expertly trained technicians support is available 12 hours a day. Noritz has also the widest variety of tankless water heaters and accessories. A variety of sizes are available for indoor, outdoor, direct vent, boiler, and energy efficient condensing models. Commercial models are available with the ASME approval.

No, we only manufacture heaters that use natural or propane gas to heat water.  However, our heaters do have components that require electricity to operate.  Electric tankless heaters are typically more expensive to operate because of their large wattage draw.  They also require substantial modification to your electrical system.

With proper maintenance the expected life of the heater is 15-20 years.

The difference between the incoming ground water temperature and the set temperature of the tankless unit.  For example, if your tankless unit was set at 120°F and your incoming ground water temperature was 50°F your temperature rise would be 70°F (120-50=70).

No, the primary firing heater rotates every 24 hours or 8 hours of combustion time.  This insures even usage of the heaters.

A qualified installer requirement will vary according to their respective states.  Make sure installer is a licensed professional and has knowledge of tankless water heaters.

Although not recommended, heaters can be painted as long as safety labels and vents are not covered.   

Use the following chart to determine which accessories work for which units:

Tankless water heaters heat on demand. The water is heated as it flows through the unit. Automated valves control water and gas flow so that your water comes out at the temperature you set it to.

Noritz sells through professional distribution only, not directly to customers.

A btu (British Thermal Unit) is the amount of heat energy needed to raise the temperature of one pound of water by one degree F. The btu/h is a measure of btus used in one hour.

Installers are rated by their experience installing Noritz heaters. After a certain amount of heaters are installed a ‘Qualified Installer’ title is earned, additional installations earn the ‘Power Installer’ title.  

ASME heaters are manufactured according to ASME quality control standards.  These ASME heaters also carry a superior commercial warranty (5 years on heat exchanger and parts) as compared to our non-ASME models (3 years on heat exchanger and parts); they also have stainless steel cases.

The freeze prevention will work as long as there is electrical power. Do not install unit outdoors in climates where temperature falls below – 4 Degrees F in the absence of wind. Do not install inside in environments where outside temperature falls below – 30 degrees F. 

Consult with your local codes.  It is recommended to avoid installing near bedrooms, as there will be some noise during operation.

Yes, but there are simple adjustments that need to be made if installed above 2,000ft.

Yes, a commercial grade heater can be installed if necessary in a residential application.

Please refer to your local codes. 

Consult with local codes. 3/8 inch high temperature silicon rubber tubing is recommended.

Yes, our Direct Vent and Outdoor models can be installed in a manufactured/mobile home.

They can be installed in a mechanical closet as long as there is a sufficient supply of air. Refer to the combustion air specifications in the Vent Pipe Installation section of your installation manual.

Check local codes if installing a unit over 200,000 BTU/H

In some states it is not required by law but it is recommended to get ASME heater/s for your restaurant because they have a 5 year parts / 5 year heat exchanger warranty.

The filter, located on the cold water inlet fitting, should be checked for debris about once a year.

The front cover, fan, and venting should be checked for dust and debris. Depending on water quality, a heat exchanger flush may be necessary as well.

A pump should be sized to overcome the head losses of the water heater and frictional piping losses.  Typically, a pump should be sized to provide 2 gpm of flow based on 10 feet of head loss plus additional losses. 

It is not necessary; the 8-10 gallon storage tank alleviates cold water sandwiching effects that occur in some installations.  A storage tank should not be used in commercial applications, or in plumbing systems that have piping larger than ¾”.  It is meant for comfort purposes only and is not necessary for correct operation of a recirculation loop.

Our tankless heaters have a factory default setting of 120°F.  In order to increase the temperature for the NR66, NR71, NR98 and NR111 series without a remote, use the following procedures:

             NR66/ NR71 Series

1.       Unplug the unit

2.       Locate the jumper clips labeled 130°F/140°F in a small bag attached inside the unit on the left hand wall.

3.       Plug the desired temperature jumper into the slot between the two screws labeled remote control and power the unit up.

NR98/ NR111 Series

1.       Unplug the unit

2.       Locate the “Water Temperature Adjustment Connector”

3.       Locate the 130°F, 140°F , or 180°F clips

4.       Plug the desired temperature clip into the “Water Temperature Adjustment Connector” and power the unit up

No.  The remote is water resistant; not water proof.

In the box you should find two components: 1) the remote control panel 2) the remote control cable. 

First, unplug the tankless heater.  Second, connect white connector of the remote control panel to the white connector of the remote control cable. 

There is a lockout feature on the remote controller that only allows for 120°F.  To adjust the maximum allowable temperature turn off the remote and hold the ‘flow meter alarm set’ button for at least 2 seconds. At your desired temperature turn the remote back on. You may then increase your temperature up to the maximum allowable temperature setting. Use caution when adjusting temperature, 125°F is scald skin. For temperatures above 140°F please call Noritz technical services.

Noritz sells remote cords that are 10' or 26' long.  18 gauge bell wires may be used to extend the remote up to 300' from the unit.

A tankless can help a customer achieve 50% less energy usage towards water heating, which as a whole takes up about 25% of your total energy demand.  The annual cost of a 75-gal NG tank is about $276-380.  Using an NR111-SV-NG model instead of the 75-gal tank can save 18-40% on energy usage compared to a tank while saving about $49-153 per year. There is a $300 federal tax credit for 2009 and additional saving may be found through rebates with your local gas company.  Refer to www.noritz.com/u/promos/file/2008_utility_rebates.pdf for qualifying offers.

Venting system should not be routed through any other vent, such as an existing masonry or factory-built chimney flue. Vents must be accessible for joint inspection, allow heat dissipation, and cannot exhaust directly into chimney due to back pressure.

A horizontal section of venting is strongly recommended, but if all other options are exhausted and a horizontal section cannot be installed then an angled or vertical section may be used with a vertical drain T.

The VT4-TS and VT4-TL are approved for horizontal terminations only.  Vertical installations require that 2 penetrations be made with at least 6' of horizontal separation and 1’-2’ of vertical separation.

Venting clearances vary based on the model of your heater. NRC111-SV, NRC111-DV, NCC199-SV and NCC199-DV heaters have zero clearance from combustibles when vented with PVC or CPVC material. Clearances for models NR66-SV, NR66-OD, NR71-SV, NR71-OD, NR98-SV, NR98-DV, NR98-DVC, NR98-OD, NR111-SV, NR111-DV, NH150-DV, NH199-DV are found in the following chart:

For the NC380-ASME, please refer to the following chart:

Clearances for old models may be found in the installation manuals under the ‘Vent Pipe Installation’ section.

Warranties for Noritz residential heaters cover 12 years on heat exchangers and 5 years on parts. When residential heaters are installed with recirculation or pre-heated water or in a commercial application the warranty on heat exchanger is adjusted to 3 years due to the extra use.  ASME Heaters have a 5 year warranty on the heat exchanger and parts. The typical lifespan of a tankless water heater is 15-20 years.

Water hardness is the measure of dissolved calcium, magnesium, and other minerals in your drinking water.  It is typically measured in grains of hardness which equates to 17.1 mg/L of dissolved calcium carbonate. If not treated hard water can cause mineral build-up in your heater. Mineral build-up reduces flow and produces flakes at your fixtures.

Hard water should be treated with either a water softener, which removes the hardness, or by using sequestering agents, such as the Noritz Scale Shield, that reduce the amount of scale deposits. Refer to the below tables for suggested treatment and maintenance measures to be taken based on the water hardness level.

A detailed flush procedure may be found at http://noritz.com/u/Descale%20Procedure.pdf.

To flush a Noritz heater, vinegar or a 3-1 mix of water-CLR should be pumped in the direction of water flow through a power on, gas supply closed unit for 45 minutes.  The complete flush procedure can be found online at www.noritz .com.  Go to ‘Professionals’, then mouse over ‘Support’ and select ‘Manual Documents’ in the drop down menu, then select ‘Plumbing Drawings’.  The flush procedure will be the first selection.