Noritz NR501-OD, Installation Manual

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8
Follow the instructions from the gas supplier.
Gas Type
The gas type indicated on the water heater rating plate (NG or LP) must match the type of gas being
supplied to the water heater.
Gas Conversions
If the gas type supplied does not match the gas type on the rating plate, contact your water heater supplier for
a replacement unit with the proper gas type. If a gas type conversion must be made, there are conversion
kits available for some models. [The conversion kit shall be installed by a qualified service agency in
accordance with the manufacturer’s instructions and all applicable codes and requirements of the
authority having jurisdiction. The qualified service agency is responsible for the proper installation of this
kit. Improper installation of this kit will void the warranty. Conversion kits will only be shipped directly to
the Distributor or Agency performing the conversion.]
Meter
The gas meter must be sized properly for the water heater and other gas appliances to operate properly.
Select a gas meter capable of supplying the entire btuh demand of all gas appliances in the building.
7.
Gas Piping
The guidelines and examples we have provided in this manual section are for reference only.
The sizing and installation of the gas system for this water heater, as with any gas appliance, is the
sole responsibility of the installer. The installer must be professionally trained to do such work and
must always follow all local and national codes and regulations. Gas line sizing calculations must
be performed for every installation. Please contact Noritz America at 866-766-7489 if you have
any questions or concerns.
CAUTION
Regulators
Ensure that all gas regulators used are operating properly and providing gas pressures within the specified
range of the water heater being installed. Excess gas inlet pressure may cause serious accidents.
CAUTION
Pressure
Check the gas supply pressure immediately upstream at a location provided by the gas company. Supplied
gas pressure must be within the limits shown in the specifications section with all gas appliances operating.
The inlet gas pressure must be within the range specified. This is for the purposes of input adjustment. Low
gas pressure may cause a loss of flame or ignition failure at other appliances in the home, which may result
in unburned gas in the home. Serious accidents such as fire or explosion may result.
Measuring Gas Pressure
In order to check the gas supply pressure to the unit, a tap is provided on the gas
inlet. Remove the 9/32” hex head/Philips screw from the tap, and connect a
manometer using a silicon tube. Open up at least 2 fixtures and hold in the maximum
manifold pressure button on the circuit board. Please call Noritz for details.
WARNING