Boiler Ratings & Capacities - UTICA BOILERS UB90-50 Installation 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 certi-
fied 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 Sec-
tion 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 radia-
tors, 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 pip-
ing.
BOILER RATINGS & CAPACITIES
TABLE #1 – SEA LEVEL RATINGS – NATURAL AND PROPANE GASES
++ Heating Capacity
*(MBH)
45
68
90
Net I=B=R Rating
*(MBH)
39
59
78
Btuh = British Thermal Units Per Hour
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 pub-
lished 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 boil-
ers at altitudes above 2,000 feet above sea level, the gas input
ratings (MBH) automatically reduced.
6
Shipping
Flue Dia.
Weight (lbs.)
220 2" CPVC & PVC
220 2" CPVC & PVC
220 2" CPVC & PVC