8
This low pressure oil fired hot water boiler is constructed and hydrostatically tested for a maximum working pressure of 65 PSIG (pounds per
square inch gauge) in accordance with the latest revision of the A.S.M.E. (American Society of Mechanical Engineers) Boiler and Pressure Ves-
sel Code Section IV Standards for heating boilers.
The
Heating Capacity
indicates the amount of heat available after subtracting the losses up the stack. Most of this remaining 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 base-
board, 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 system piping. The Net
I=B=R Ratings shown are based on a piping and pickup factor of 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.
BOiLer rATiNgS & CAPACiTieS
taBLE 1: OiL-FiRED HOt WatER BOiLERS - RatiNGS & caPacitiES
Number of
Sections
Firing
Rate
GPH
Input
MBTU
Heating
Capacity
MBH
Net
I=B=R
Rating
MBH
MAWP
Water
(PSIG)
Pump
PSIG AFUE
Min.
relief
Valve
Cap
Max.
Water
Temp
Chimney
Size
(Round)
Chimney
Size
(Square)
Flue
Size
4
0.75
105
90
79
65*
140
86.0
90
250°F
6”
6 3/4”
5”
5
1.00
140
120
105
65*
140
86.5
120
250°F
6”
6 3/4”
5”
6
1.30
182
157
136
65*
140
86.5
157
250°F
7”
8”
5”
7
1.65
231
198
172
65*
175
85.8
198
250°F
7”
8”
6”
* Standard boiler is supplied with a 30psig relief valve.
Standard boiler Aquastat is 220°F maximum.
For boiler dimensions, see
Table 2A
and
Figure #1
.
For burner settings & nozzle sizes, see
Oil Burner, Nozzle & Air Settings
section.
