Easy Maintenance, Low NOx, Sealed Combustion Chamber, ETL Listed, and oh yeah... THE HIGHEST NON-CONDENSING EFFICIENCY AVAILABLE!
Stack / Draft Requirements
Stack Draft (Static Pressure) at vent connector: neutral (best) to negative .1” w.c. Velocity: 20 to 30 feet-per-second @ full fire. Type B Vent (Category 1) with or without a barometric damper may be used in certain applications for natural & L.P. gas only. Boilers installed a) in high humidity or cold climates b) with modulation or high-low firing c) in battery with common stack d) with horizontal stack runs - will condense in the stack and may require category 2, 3, or 4 venting. If boiler room pressure is negative this must be factored into the stack calculation. Due to the high efficiency of Durafin boilers, every stack installation should be reviewed by a listed vent manufacturer. Support the stack independently of the boiler.
Stack Emissions @ Vent Connector
Gross Temperature Range: 275º to 325º F. Exhaust volume A.C.F.M. - see table on next page. Exhaust Velocity: 20 to 30 feet-per-second. Estimates based on high fire and Natural or L.P. gas fuels.
Combustion / Ventilation Air
Provide at least 1/2 square feet of free air opening from outside for every 1000 MBTUH input for combustion. Check local codes for exceptions. Provide the same size opening at a high point in the room for ventilation. Radiant heat loss from Durafin boilers is minimal. If additional ventilation is required it is better to force air into the room. Avoid exhaust fans whenever possible. Motorized fresh air dampers must be interlocked with boiler controls. Louvers can significantly reduce free air openings. Because Durafin has a sealed combustion chamber and operates with positive firebox pressure, a carbon monoxide detector is recommended in the boiler room.
