Boiler Ratings & Capacities - Dunkirk 90-50 Installation, Operation & Maintenance Manual

Input
Model
*(MBH)
90-50 50
90-75 75
90-100 100
* 1 MBH = 1,000 Btuh
These low pressure gas-fired hot water boilers are design certified
by CSA International for use with natural and propane gases. The
boilers are constructed and hydrostatically tested for a maximum
working pressure of 50 psig (pounds per square inch gage) in
accordance with A.S.M.E. (American Society of Mechanical
Engineers) Boiler and Pressure Vessel Code Section IV Standards for
heating boilers.
++ AFUE (Annual Fuel Utilization Efficiency) and Heating Capacity
is based on the D.O.E. (Department of Energy) test procedure.
The Boilers are certified in accordance with ANSI (American
National Standards Institute) Z21.13 standards as gas-fired, direct
vent, condensing, hot water boilers.
The Heating Capacity indicates the amount of heat available after
subtracting the losses up the stack. Most of this heat is available to
heat water. A small portion is heat from the jacket and surfaces of
the boiler, and it is assumed that this heat stays in the structure. The
Net I=B=R Rating represents the portion of the remaining heat that
can be applied to heat the radiation or terminal units (i.e. finned
tube baseboard, cast iron radiators, radiant floor, etc.). The difference
between the Heating Capacity and the Net I=B=R Rating, called the
piping and pickup allowance, establishes a reserve for heating the
volume of water in the system and offsetting heat losses from the
piping.
boiler raTings & CapaCiTies
TABLE #1 – SEA LEVEL RATINGS – NATURAL AND PROPANE GASES
++ Heating Capacity
*(MBH)
45
68
90
Btuh = British Thermal Units Per Hour
Net I=B=R Rating Shipping
*(MBH) Weight (lbs.)
39
59
78
The Net I=B R Ratings shown are based on a piping and pickup
factor of 1.15 in accordance with the I=B=R Standard as published
by the Hydronics Institute. The Net I=B=R Rating of the boiler
selected should be greater than or equal to the calculated peak
heating load (heat loss) for the building or area(s) served by the
boiler and associated hot water heating systems. The manufacturer
should be consulted before selecting a boiler for installations having
unusual piping and pickup requirements.
The boilers are factory equipped for operation at altitudes ranging
from 0-2,000 feet above sea level. For use of these boilers at altitudes
above 2,000 feet above sea level, the gas input ratings (MBH)
automatically reduced.
5
Flue Dia.
220 2" CPVC & PVC
220 2" CPVC & PVC
220 2" CPVC & PVC