6
Table 2 - 90 - 50/75/100 SERIES 2 NATURAL GAS
MODEL 90-50
Stock Factory Btu Value of Natural Gas++
Settings 750 850 950 1000 1050
Altitude in Ft. 0-5,000 5,000-10,000
Normal Input (MBH) 50 – – – – –
Manifold Pressure In W.C. 2.5 4 4 3.5 2.5 2.5
Orifi ce 43331094 43331094
MODEL 90-75
Stock Factory Btu Value of Natural Gas++
Settings 750 850 950 1000 1050
Altitude in Ft. 0-5,000 5,000-10,000
Normal Input (MBH) 75 – – – – –
Manifold Pressure In W.C. 2.5 3.5 3.5 2.5 2.5 2.5
Orifi ce 43331092 43331092
MODEL 90-100
Stock Factory Btu Value of Natural Gas++
Settings 750 850 950 1000 1050
Altitude in Ft. 0-5,000 5,000-10,000
Normal Input (MBH) 100 – – – – –
Manifold Pressure In W.C. 2.5 3.5 3.5 2.5 2.5 2.5
Orifi ce 43331090 43331090
++Contact local gas utility or distributor for Btu value of gas.
BOILERS FOR USE AT HIGH ALTITUDE - UNITED STATES INSTALLATIONS
• Boilers (with exception of 90-75 propane (LP) product)
are factory equipped for operation at altitudes ranging
from 0-10,000 feet above sea level.
• No changes to factory settings are required for installa-
tions from 0-5,000 feet above sea level.
• For altitudes from 5,000-10,000 feet above sea level
gas manifold pressure needs to be adjusted based upon
calorifi c (Btu) value of supply gas (contact local gas
utility or distributor for this value).
• For specifi c settings refer to Table 2 for natural gas
applications and
Table 3, Page 7
for propane (LP) gas
applications.
• Instructions on how to adjust gas manifold pressure
settings see
Figure 27 and Figure 28, Page 44
.
Note 90-75 propane (LP) applications for 5,000 - 10,000
feet above sea level require orifi ce change as well as gas
manifold pressure adjustment based upon calorifi c (Btu)
value of supply gas.
Refer to
Table 2
and Table 3 for high altitude orifi ce part
number. For replacing orifi ce refer to specifi c instructions
included with conversion kit.