AERCO BMK 1.5 LN July 2011 - Manual (Page 27)

CHAPTER 2: INSTALLATION
PR2: 05/09/12 Page 27 of 152
Benchmark 1.5LN Low NOx Boiler
Operation and Maintenance Manual
OMM-0041_0D
GF-120
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288
The AERCO Benchmark 1.5 Boiler is UL listed for 100% sealed combustion. It can also be
installed using room air, provided there is an adequate supply. (See paragraph 2.13.3 for more
information concerning sealed combustion air). If the sealed combustion air option is not being
used, an inlet screen will be attached at the air inlet on the top of the unit
The more common methods of supplying combustion air are outlined below. For more
information concerning combustion air, consult the AERCO Benchmark Venting and
Combustion Air Guide, GF-2050.
Combustion Air From Outside the Building 2.13.1
Air supplied from outside the building must be provided through two permanent openings. Each
opening must have a free area of not less than one square inch for each 4000 BTU/H boiler
input. The free area must take into account restrictions such as louvers and bird screens. For
Canada installations, refer to the requirements specified in CSA B149.1-10, 8.4.1 and 8.4.3.
Combustion Air From Inside The Building 2.13.2
When combustion air is provided from within the building, it must be supplied through two
permanent openings in an interior wall. Each opening must have a free area of not less than
one square inch per 1000 BTU/H of total boiler input. The free area must take into account any
restrictions such as louvers.
Sealed Combustion 2.13.3
The AERCO Benchmark 1.5 Boiler is UL listed for 100%-sealed combustion. For sealed
combustion installations, the screen on the air inlet duct of the unit must be removed. The inlet
air ductwork must then be attached directly to the unit’s air inlet.
In a sealed combustion air application, the combustion air ducting pressure losses must be
taken into account when calculating the total maximum allowable venting run. See the AERCO
Benchmark Venting and Combustion Air Guide, GF-2050. When using the boiler in a sealed
combustion air configuration, each unit must have a minimum 6 inch diameter connection at the
unit.
Temporary Combustion Air Filtering During Construction 2.13.4
When the Benchmark 1.5 Boiler is used to provide heat temporarily during ongoing building
construction, accumulated drywall dust, sawdust and similar particles can accumulate in the
unit’s combustion air intake filter and block combustion air flow. In these situations, AERCO
recommends that a disposable air intake filter be installed, temporarily, above the boiler
combustion air inlet.
AERCO recommends that the temporary air filter be cut from a McMaster-Carr part no.
2122K315 Polyester Air Filter Roll Tackfield, ½” thick, 16” wide, or equivalent. Cover the
Benchmark 1.5 air inlet with the blue side of the filter material facing outward to hold the dust on
the outside surface. Maximize the surface area of the filter covering the 8" diameter opening by
creating a dome out of the filter material.
Cover the flared duct opening with the blue side facing outward. During construction check the
filter for dust accumulation and replace it when the accumulation becomes noticeable.
2.14 BENCHMARK PUMP RELAY OPTION
An optional Benchmark pump relay allows the user to turn a pump on/off and open/close a motorized
valve as the boiler cycles on and off on demand. The Pump Delay Timer feature allows the user to keep
the pump running and keep the motorized valve open for up to 30 minutes after the boiler has shut down
and the demand is satisfied.
The Benchmark pump relay (SPDT) contact is rated for: