8
About the Boiler
General Specifications
Item
NFB-175
NFB-200
Dimensions
17.3 in (W) x 17.3 in (D) x 27.6 in (H)
Weight
123 lb (56 kg)
Installation Type
Indoor Wall-Hung
Venting Type
Forced Draft Direct Vent
Ignition
Electronic Ignition
Natural Gas Supply Pressure (from source)
3.5 in–10.5 in WC
Propane Gas Supply Pressure (from source)
8.0 in–13.5 in WC
Natural Gas Manifold Pressure
-0.05 to -0.70 in WC
-0.05 to -0.20 in WC
Propane Gas Manifold Pressure
-0.10 to -0.68 in WC
-0.10 to -0.45 in WC
Gas Connection Size
3/4 in NPT
Power Supply
Main Supply
120V AC, 60Hz
Maximum Power
Consumption
Less than 15 amperes
Materials
Casing
Cold-rolled carbon steel
Heat Exchangers
Stainless Steel
Venting
Exhaust
2 in or 3 in PVC, CPVC, approved polypropylene*
2 in or 3 in Special Gas Vent Type BH (Class III, A/B/C)
2 in or 3 in Stainless Steel
Intake
2 in or 3 in PVC, CPVC, polypropylene
2 in or 3 in Special Gas Vent Type BH (Class III, A/B/C)
2 in or 3 in Stainless Steel
Vent Clearance
0 in to combustibles
Safety Devices
Flame Rod, APS, Ignition Operation Detector
Water Temperature High Limit Switch, Exhaust Temperature High Limit Sensor, Water
Pressure Sensor
Temperature Setting Range
Item
Temperature Setting Range
Remarks
Space Heating
Supply
77–194°F (25-90°C)
Actual supply and return temperatures vary
depending on the selected outdoor reset
curve.
Return
68–158°F (20-70°C)
Note
For more information about the space heating temperature setting range, refer to “11.3.3 Setting the Space Heating Operation” on
