Super Hot AAA-3000 series, Installation And Service Manual

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AAA Series Gas Boiler – Installation and Service Manual
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4.6 CHECK INPUT & ORIFICES
For safety, the input shown on rating plate must not be exceeded. Check with the table below that
the orifice size and input rate shown on your boiler rating plate match your application, i.e. boiler model,
fuel type, and altitude. See AAA Specifications to find a boiler model's input rate.
FOR CANADA
Natural Gas Propane
Model
0 to 2,000 feet 2,000 to 4,500 feet 0 to 2,000 feet 2,000 to 4,500 feet
AAA
#28 orifice
standard input Contact Allied Eng. sales
office for details
#46 orifice
Contact Allied Eng.
sales office for details
FOR UNITED STATES
Natural Gas Propane
Model
0 to 2,000 feet Over 2,000 feet 0 to 2,000 feet Over 2,000 feet
AAA
#28 orifice
standard input
Input must be reduced
4% for each 1000 ft
above sea level. *
#46 orifice
Input must be reduced
4% for each 1000 ft
above sea level. *
*Reference National Fuel Gas Code ANSI Z223.1 , 8.1.2 High Altitude.
Small adjustments to the input rate can be made by varying the manifold pressure. Normally it should be
adjusted no more than 0.2 inch w.c. for natural gas or 0.5 inch w.c. for propane from the manifold
pressure specified on the rating plate.
WARNING
Exceeding the allowable input rate can produce dangerous concentrations of carbon monoxide,
and cause the boiler to overheat resulting in severe personal injury, death or substantial
property damage. Carbon monoxide is a lethal, colorless and odorless gas.
Input Rate Test
Consult gas company to determine the heating value of the gas supplied in Btu per cubic feet. Operate
boiler for 15 minutes starting with all parts at room temperature and check input by clocking gas meter
with all other gas appliances turned off, including their pilot flames. Use the following formula:
INPUT (Btu/h) =
Clocked Seconds
Timed) Feet Cubic of (Number x Gas) of Value (Heating (3600)
×
To ensure accuracy for rating, clock enough cubic feet of gas so that there is at least one revolution of the
test dial and the clocked time is at least 60 seconds.
Two Stage or Full Modulating Gas Valve
When a two stage or modulating gas valve is used, it must be checked for correct input at both "High" and
"Low" fire settings. The clocked input rate MUST be within the "Minimum Input" and the "Input" as
specified on the boiler's rating plate. To force a two stage or full modulating gas valve to low fire, see the
valve manufacturer's instructions. Perform the Input Rate Test described above and adjust manifold
pressure of High and Low settings as necessary. For altitudes above 2000 feet, DO NOT derate the
"Minimum Input" rate.