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GAS SUPPLY AND GAS PIPE SIZING
-General-
•
Do not use this water heater with any gas other than the one listed on the rating
plate unless the water heater has been properly converted.
•
Ensure that any and all gas regulators used are operating properly and providing
gas pressures within the specified range shown below. Excess gas inlet pressure
may cause serious accidents.
•
If your water heater needs a gas conversion, refer to the instructions supplied with
the heater and included with the conversion components.
•
Failure to observe these warnings could result in severe personal injury, carbon
monoxide poisoning, or death.
WARNING
•
The minimum and maximum inlet gas pressures
Gas type
Inlet gas pressure
Natural Gas
Min. 4.0” W.C. (1.00 kPa) – Max. 10.5” W.C. (2.61 kPa)
Propane
Min. 8.0” W.C. (1.99 kPa) – Max. 14.0” W.C. (3.48 kPa)
•
Inlet gas pressures that fall outside the range of values listed above may adversely affect the
performance of the water heater. These pressures are measured when the water heater is in full
operation and in standby.
•
Inlet gas pressure must not exceed the above maximum values; gas pressure above the specified range
will cause dangerous operating conditions and damage to the unit.
•
Until testing of the main gas line supply pressure is completed, ensure the gas line to the water heater
is disconnected to avoid any damage to the water heater.
•
If the gas supply pressure to the heater is greater than the specified maximum, a field-supplied
regulator is required. The regulator must lower the gas pressure within the approved range.
•
Install the gas regulator according to the manufacturer's instructions.
•
The regulator must be sized for the water heater input and provide the specified pressures that
are listed on the rating plate.
•
In the absence of minimum install distance, it is recommended that there is at least 3 ft (1 m) of
piping between the regulator outlet and the water heater's inlet gas connection.
-Gas connections-
1. Install a full port, manual gas shutoff valve between the water heater and the gas supply line.
2. When the gas connections are completed, it is necessary to perform a gas leak test either by applying
soapy water to all gas fittings and observing for bubbles or by using a gas leak detection device.
•
The water heater and its individual shutoff valve must be disconnected from the gas supply
piping system during any pressure testing of that system at test pressures in excess of 1/2 psi
(3.5 kPa).
•
The water heater must be isolated from the gas supply piping system by closing its individual
manual shutoff valve during any pressure testing of the gas supply piping system at test
pressures equal to or less than 1/2 psi (3.5 kPa).
3. Always purge the gas line of any debris and/or water before connecting to the gas inlet.
Size the gas pipe to supply the necessary volume of gas for the water heater. Refer
to and follow the requirements listed in the current edition of ANSI Z223.1/NFPA
54 (USA), B149.1 (Canada), or local codes. Otherwise, flow capabilities and output
temperatures will be limited.
NOTICE
Installation
Installation Manual
