connection.
2.2.10
Humidifiers
Factory-assembled, single or multiple units as required to obtain the
capacities indicated.
2.2.10.1
Evaporative Pan
UL 998. [UL listed and rated as indicated.] Units shall have submerged
[steel coils] [or] [electric heating elements] to evaporate water from pans
into the surrounding air. [Steam coils shall be of copper construction
with pan of copper or 300 series stainless steel per ASTM A 167.] Provide
low water cut-off switch.
2.2.10.2
Steam Grid
**************************************************************************
NOTE: Steam containing amines should not be
injected directly into the air stream. A dedicated
"clean steam" boilers is recommended to supply steam
to this equipment.
**************************************************************************
Units shall inject steam directly into the air stream. Factory mounted [in
plenum with drain pan for draw-thru units] [in diffuser section of
blow-thru units].
a.
For single grid units, equip each unit with a single [copper]
[galvanized steel] distribution grid with pipe connection on one
end and cap on the other end. Evenly space orifices along grid
length. Provide automatic steam control valve and condensate
traps. House grid in [copper] [galvanized steel] enclosures with
built-in condensate drain connection for enclosed-grid type and
wrap grid with wicks for exposed-grid type.
b.
For packaged units, equip each unit with provisions to trap out
and reevaporate condensate and to supply dry steam for a single
distribution grid. Provide modulating [electric] [electronic]
[or] [pneumatic] steam-control valve, steam-jacket with condensate
drain, and condensate trap.
c.
Electronic Electrode Steam Units: Self-contained, electronic
steam generators with steam output as indicated and equipped with
disposable tank. Provide each unit with a solid state energy
saving control circuit to control steam output and compensate for
changing water conditions without chemical additives. Include an
integral control and monitoring panel, with a capacity meter, a
"change cylinder (container)" indicator, a capacity adjustment
control adjusting from 20 to 100 percent of rated output capacity,
an on-off drain switch, and an on-auto push button with indicator
light. Equip each unit with double-wall insulated steam supply
hose, a steam distributor, an automatic fill with cleanable
strainers, or an automatic drain valve.
2.2.10.3
Mechanical Water-Spray
UL 998 and UL listed, [space] [or] [duct] units. Equip each unit with a
water reservoir with float-controlled makeup valve, inlet and overflow
SECTION 15720N
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