Install Instructions

6
Ratings
Notes:
1. As an Energy Star Partner, the manufacturer has determined
that Noble Fire Tubes meet the Energy Star guidelines for
energy efficiency.
2. The ratings are based on standard test procedures prescribed
by the United States Department of Energy.
3. Net AHRI ratings are based on net installed radiation of
sufficient quantity for the requirements of the building
and nothing need be added for normal piping and pickup.
Ratings are based on a piping and pickup allowance of 1.15.
4. Noble Fire Tubes require special gas venting. Use only the
vent materials and methods specified in the Noble Fire Tube
Installation and Service Manual.
5. Standard Noble Fire Tubes are equipped to operate from sea
level to 4,500 feet only with no adjustments. The boiler will
de-rate by 4% for each 1,000 feet above sea level up to 4,500
feet.
6. High altitude Noble Fire Tubes are equipped to operate from
3,000 to 9,600 feet.  e boiler will de-rate 1.7% between
5,000 to 9,600 feet. For any units installed past 9,600 feet
there is an additional de-rate of 4% per 1,000 feet beyond
9,600 feet per the National Fuel Gas Code. Appliances
con gured for high altitude shall not be installed below 3000
feet.
The operation given in this manual remains the same as the
standard boilers. A high altitude label (as shown in FIG. A)
is also affixed to the unit.
De-rate values are based on proper combustion calibration
and
CO
2
’s adjusted to the recommended levels.
For installations above 9,600 feet, please consult the factory.
Maximum allowed working pressure is located on the rating plate.
NOTICE
AHRI Rating
Model Number
Note: Change “N”
to “L” for L.P. gas
models.
Input
MBH
(Note 5)
Heating
Capacity
MBH
(Note 2, 7)
Net
AHRI
Ratings
Water,
MBH
(Note 3, 7)
AFUE
%
(Note 1, 7)
Min
Max
NKB80N 8.3 80 74 64 95.0
NK(B,C)110N 11 110 102 89 95.0
NK(B,C)150N 15 150 139 121 95.0
NK(B,C)199N 19.9 199 185 161 95.0
7. Ratings have been confirmed by the Hydronics Institute,
Section of AHRI.
8. The manual reset high limit provided with the Noble Fire
Tube is listed to UL353.
Other Specifications
Boiler Water
Content Gallons
SH Water
Connections
NPT = Combi
Sweat = Boiler
DHW Water
Connections
Combi Only
Gas
Connections
Vent/Air
Size
(Note 4)
1.2 1" -- 1/2" 3"
1.4 1" 3/4" 1/2" 3"
2.0 1" 3/4" 1/2" 3"
2.7 1" 3/4" 1/2" 3"
Figure A High Altitude Label Location
UNIT EQUIPPED FOR
HIGH ALTITUDE
3,000 FT. TO 9,600 FT.
A
S
M
E
H
LOW LEAD CONTENT
Installation & Service Manual
FIRE TUBE
™