equipped with quick-opening mechanism for changing filter media. The air
flow capacity of the filter shall be based on net filter face velocity not
exceeding [1.5] [_____] m/s [300] [_____] fpm, with initial resistance of
[32] [_____] Pa [0.13] [_____] inches water gauge. The MERV shall be not
less than [_____] when tested according to ASHRAE 52.2.
2.7.3.6
Automatic Renewable Media Filters
Automatic, renewable media filters shall consist of a horizontal or
vertical traveling curtain of adhesive-coated bonded fibrous glass supplied
in convenient roll form. Operation and maintenance requirements of the
filter shall not require water supply, sewer connections, adhesive
reservoir, or sprinkler equipment. Basic frame shall be fabricated of not
less than 2 mm 14 gauge galvanized steel. Filters shall be sectional
design with each section of each filter fully factory assembled, requiring
no field assembly other than setting in place next to any adjacent sections
and the installation of media in roll form. Each filter shall be complete
with initial loading of filter media drive motor adequate to handle the
number of sections involved, and [painted steel] [stainless steel] control
box containing a warning light to indicate media runout, a runout switch,
and a Hand-Off-Auto selector switch. Media feed across the filter face
shall be in [full-face increments] [increments] automatically controlled as
determined by [filter pressure differential] [time interval control] [time
interval control with pressure override] [photo electric control] to
provide substantially constant operating resistance to airflow and varying
not more than plus or minus 10 percent. Media shall be rolled or enclosed
in such a way that collected particulates will not re-entrain. Rolls of
clean media, no less than 19.8 m 65 feet long, shall be rerolled on
disposable spools in the rewind section of the filter after the media has
accumulated its design dirt load. Rewind section shall be equipped with a
compression panel to tightly rewind used media for ease of handling. Media
shall be of continuous, bonded fibrous glass material, shall be UL Class 2,
and shall not compress more than 6 mm 1/4 inch when subjected to air flow
at 2.54 m/s 500 fpm. Media shall be factory charged with an odorless and
flame retardant adhesive which shall not flow while in storage nor when
subjected to temperatures up to 79.4 degrees C 175 degrees F. Media shall
be supported on both the leaving and entering air faces. The initial
resistance of the clean media shall not exceed 45 Pa 0.18 inch water gauge
at its rated velocity of 2.54 m/s 500 fpm. Control shall be set so that
the resistance to air flow is between 100 and 125 Pa 0.40-and 0.50 inch
water gauge unless otherwise indicated. Dust holding capacity under these
operating conditions, when operating at a steady state with an upper
operating resistance of 125 Pa 0.50 inch water gauge, shall be at least 592
(55) grams of ASHRAE Standard Test Dust per square meter (foot) of media
area, when tested according to the dynamic testing provisions of ASHRAE 52.2.
Average arrestance under these conditions shall be 80 percent. When used
in conjunction with factory fabricated air handling units, the horizontal
type automatic renewable media filters shall be dimensionally compatible
with the connecting air handling units. Horizontal type filter housings
shall have all exposed surfaces factory insulated internally with 25 mm 1
inch, 24 kg/cubic meter 1-1/2 pound density neoprene coated fibrous glass
with thermal conductivity not greater than 0.04 W/m-K 0.27 Btu/hour/degree
F/square foot/inch of thickness. Access doors for horizontal filters shall
be of double wall construction as specified for plenums and casings for
field-fabricated units in paragraph DUCT SYSTEMS.
2.7.3.7
Electrostatic Filters
Electrostatic filters shall be the combination dry agglomerator/extended
SECTION 15895
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