Vent & Combustion Air System Design Requirements - Aerco Benchmark Platinum Series Pre-Installation Application Manual

Benchmark Series Pre-Installation Venting & Combustion Air
19. Vent & Combustion Air System Design Requirements
The minimum exhaust vent and combustion air duct sizes for Benchmark Low NOx boilers
models are as follows:
Model Combustion Air Duct
BMK 750 6 inch (15.2 cm)
BMK 1000 6 inch (15.2 cm)
BMK 1500 6 inch (15.2 cm)
BMK 2000 8 inch (20.3 cm)
BMK 2500 8 inch (20.3 cm)
BMK 3000 8 inch (20.3 cm)
BMK 5000
14 inch (35.6 cm)
BMK 6000
*
Optional 12 inch (30.5 cm) diameter exhaust venting requires a 12" (30.5 cm) vent adapter. Consult
your local AERCO sales representative or vent manufacturer or AERCO International for more
information on the 12" (30.5 cm) adapter.
A 1/4-inch (6.35 mm) NPT combustion test hole is provided on each unit's exhaust manifold
connection (See Figures 8a, 8b, 8c and 8d). A 24 inch (61 cm) length of straight vent is
required downstream of the exhaust manifold, as illustrated in these figures.
The vent system should always be pitched up 1/4 inch per foot (21 mm per m) of run towards
the vent termination to enable condensate to drain back to the unit for disposal. Low spots in the
vent must be avoided. Periodic inspection must be performed to assure correct drainage.
Benchmark vents must not be interconnected to those of other manufacturers' equipment.
Horizontal vent and ductwork must be supported to prevent sagging, in accordance with local
code and the vent manufacturer's requirements. Vertical vent and ductwork must be supported
to prevent excessive stress on the horizontal runs. The exhaust manifold and inlet air adapter
must never be used as weight-supporting elements. The supports must be so arranged and the
overall layout designed to assure that stresses on the vent and combustion air connections are
minimized.
The vents and combustion air ducts may be insulated in accordance with the vent
manufacturer's instructions and local codes.
Page 16 of 51 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913
9/14/2018
Minimum Diameter
Exhaust Vent Diameter
6 inch (15.2 cm)
6 inch (15.2 cm)
6 inch (15.2 cm)
8 inch (20.3 cm)
8 inch (20.3 cm)
8 inch (20.3 cm)
14 inch (35.6 cm) (<9ppm NO
* 12 inch (30.5 cm) optional (Standard <20ppm NO
Phone: 800-526-0288
Optional Calibration)
x
emissions only)
x
TAG-0022_0Z
GF-2050