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2 - BOILER RATINGS AND CAPACITIES
Table 2 - 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
*HIGH
ALTITUDE
INPUT
(3)
Mbh
INPUT
(3)
Mbh
HEATING
CAPACITY
(3)
Mbh
NET AHRI
RATING
*HIGH
ALTITUDE
INPUT
(3)
Mbh
INTERMITTENT
IGNITION WITH
VENT DAMPER
OMGC-8
262.5
220
191
236
245
206
179
220
83.9
OMGC-9
299
251
218
269
280
235
204
252
83.7
†
Input rating for sea level to 2,000 ft. (610m) above sea level.
• United States,
over 2000 ft (610m) above sea level. Reduce input rate 4% for every 1000 ft (304m) above sea
level.
• *Canada,
2000 ft (610m) to 4500 (1350m) above sea level, reduce input per table. Over 4500 ft (1350m) above
sea level. Contact Provincial authority having jurisdiction.
+ Heating Capacity based on D.O.E. (Department of Energy) test procedure.
(1)
Add model number suffice ‘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 orifice 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, ANSI Z223.1/NFPA 54, or manufacturer for correct orifice sizing information.
In Canada, a high altitude conversion kit is available to convert to altitudes of 2,000 to 4,500 feet above sea level. Please
consult your dealer.
