Flue Gas Discharge And Air Supply; General; Boiler Venting Types - Absolute ABS-1500 Installation And Operating Manual

4.3 Flue gas discharge and air supply

4.3.1 General

The Absolute Boiler is suitable for both conventional room-supplied or sealed combustion. It is listed as a 100% sealed
combustion boiler. Sealed combustion terminals should comply with the local and national codes. Any horizontal pipe-
work in the flue gas discharge system should slope towards the boiler. This horizontal venting must be properly secured
to the building as per the vent manufacturers installation manual. The horizontal venting must not have low spots
and must not sag. Horizontal pipe-work in the air supply system should slope towards the supply opening and may
require a drain point at the low point. Care should be taken when locating flue exit positions as a vapor plume will be
visible when the boiler is operational (flue gas temperature will be less than 170°F [77°C] resulting in the water vapor
condensing out on contact with the air).

4.4 Boiler Venting Types

Flue gas venting:
- Use only an approved gas vent category II and IV. Rated for 110°C/230°F
- The venting shall be sized by a chimney venting specialized or professional engineer using methods of vent
calculations that are acceptable to the National and local codes have jurisdiction. The vent shall then extend
vertically 5 ft (1.5M) minimum through the roof ceiling.
- Category II-Negative breaching pressure ranging from 0 to -0.29 inches water column(0 to 22mbar)
- Category IV-Positive breeching pressure ranging from 0 to +0.20 inches water column (0 to 50 mbar)
- Follow the vent manufactures recommended and supplied instructions regarding; vent connection, cleaning, sealing
and support.
DANGER
PVC or CPVC should never be used in the Absolute Boiler. PVC and CPVC is not rated for the potential flue temperatures
and failure of this venting material can cause severe personnel injury or death! Use AL 29-4C or stainless steel
equivlent venting.
Conventional Chimney Applications:
A vertical chimney-vent system with the air supply, required for combustion, provided within the boiler room or
combustion air source provided into the room.
Direct Vent [Side wall] Applications:
A horizontal vent system with the air supply, required for combustion, provided within the boiler room or combustion
air sources provided into the room. Ensure proper reassembly and resealing of the vent-air intake system.
-Sealed Combustion Systems Applications:
Vertical or horizontal venting systems for both, the flue gases and combustion air operating at two different pressure
zones or vent terminal locations.
Seal Combustion System Applications:
A vertical or horizontal venting system for both, the flue gases
and combustion air at same termination and pressure level.
Absolute Boilers ABS 1500-2000-2500-3000-4000
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