Boilers for use at high altitude – Dunkirk WPSB Series II User Manual
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BOILER RATINGS AND CAPACITIES
Table 1 - Ratings and Capacities
BOILER
MODEL
NUMBER
(1)
† NATURAL GAS
† PROPANE GAS
AFUE
Input
(3)
Mbh
Heating
Capacity
(3)
Mbh
(2)
NET AHRI
RATING
Water,
(3)
Mbh
INPUT
(3)
Mbh
HEATING
CAPACITY
(3)
MBH
(2) NET
AHRI
RATING
(3)
Mbh
INTERMITTENT
IGNITION
WITH VENT
DAMPER
WPSB-3
75
63
55
70
59
51
84.0
WPSB-4
112.5
94
82
105
88
77
84.0
WPSB-5
150
126
110
140
118
103
84.1
WPSB-6
187.5
157
137
175
147
128
84.1
WPSB-7
225
188
163
210
176
153
84.0
WPSB-8
262.5
220
191
245
206
179
83.9
WPSB-9
299
251
218
280
235
204
83.7
†
For altitudes above 2,000 ft. rating should be reduced at the rate of 4% for each 1,000 ft. above sea level.
Heating Capacity is based on D.O.E. (Department of Energy) test procedure.
(1)
Add model number suffi x ‘P’ for Propane.
(2)
Net AHRI Water rating shown based on piping and pickup allowance of 1.15. Consult manufacturer before
selecting boiler for installations having unusual piping and pickup requirements, such as intermittent
system operation, extensive piping systems, etc.
(3)
MBH = 1,000 Btuh = British Thermal Unit Per Hour
-
Ratings marked “Net AHRI Ratings” indicate amount of remaining heat input used to heat radiation or
terminal units. Net AHRI Ratings shown are based on allowance of 1.15 in accordance with factors shown on
AHRI Standard as published by The Hydronics Institute.
-
Selection of boiler size should be based upon “Net AHRI Rating” being equal to or greater than calculated
heat loss of the building.
-
Consult manufacturer before selecting boiler for installations having unusual piping and pickup requirements.
BOILERS FOR USE AT HIGH ALTITUDE
Boiler is factory equipped for use at altitudes of 0-2,000 feet above sea level.
For use at altitudes above 2,000 feet above sea level, input ratings are reduced by change in main burner
orifi ce size.
For altitudes above 2,000 feet above sea level, input ratings should be reduced at rate of 4% for each 1,000
feet above sea level. Consult National Fuel Gas Code (NFPA54/ANSI Z223.1-latest edition), or manufacturer
for correct orifi ce sizing information.