Dunkirk DWB Series - Manual (Page 34)

12.1 Ratings and Capacities
• Constructed and hydrostatically tested for maximum
allowable working pressure of 43.5 psig (pounds per
square inch gauge)
43.5 psig (.30MPa) in accordance
with ASME Boiler and Pressure Vessel Code, Section IV,
Rules for Construction of Heating Boilers.
• USA - Input rates are derated 4% for each 1000 ft (300m)
above sea level, beyond 2000 ft (600m).
• CANADA - Ratings in table 13 used for elevations up to 2000
ft (600m) above sea level
- For elevations between 2000 ft (600m) and 4500
ft (1350m), derate 10% using high altitude kit.
- Contact Provincial authority having jurisdiction
for installations above 4500 feet (1350 m) above
sea level.
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SEA LEVEL RATINGS
NATURAL AND PROPANE GASES
Size
Boiler Input Rate
(MBH) (1)
Heating
Capacity
(MBH) (1)(2)
Net AHRI
Rating, Water
(MBH) (1)(3)
AFUE (2)
Maximum Minimum
CHB-100 100 31.5 85 73.0 85
CHB-130 130 43.5 110 96.0 85
(1) 1000 Btu/hr (British Thermal Units Per Hour)
(2) Heating Capacity and AFUE (Annual Fuel Utilization Effi ciency) are based on DOE (Department of Energy) test
procedures.
(3) Net AHRI Ratings based on piping and pickup allowance of 1.15. Contact Technical Support before selecting boiler for
installations having unusual piping and pickup requirements, such as intermittent system operation, extensive piping systems,
etc.
12 - RATINGS AND CAPACITIES
Table 8 - Sea Level Ratings