93
b. Evaporator coils shall be leak tested to 150 psig, pressure tested to 450 psig, and qualified to UL 1995 burst
test a t 1775 psig.
c. Condenser coils shall be leak tested to 150 psig, pressure teste d to 650 psig, and qualified to UL 1995 burst
test a t 1980 psig.
2. Optional Pre--coated aluminum--fin condenser coi ls (3 Phase Models Only):
a. Shall have a durable epoxy--phenolic coating to provide protection in mildly corrosive coastal environ-
ments.
b. Coating shall be applied to the aluminum fin stock prior t o the fin stamping proce ss to c reate an inert barri-
er bet we en the aluminum fin and copper tube.
c. Epoxy--phenolic barrier shall minimize galvanic action between dissimilar metals.
3. Optional Copper--fin evaporator and condenser coils (3 Phase Models Only):
a. Shall be constructed of copper fins mechanically bonded to copper tubes and copper tube sheets.
b. Galvanized steel tube sheets shall not be acceptable.
c. A polymer strip shall prevent coil assembly from contacting the sheet metal coil pan to minimize potential
for galvanic corrosion between coil and pan.
4. Optional E--coated aluminum--fin evapora tor and condenser coils (3 Phase Models Only):
a. Shall have a flexible epoxy polymer coat ing uniformly applie d to all coil surfac e areas without material
bridging between fins.
b. Coating process shall ensure complete coil encapsulation of tubes, fins and headers.
c. Color shall be high gloss black with gloss per ASTM D523--89.
d. Uniform dry film thickness from 0.8 to 1.2 mil on all surface areas including fin edges.
e. Superior hardness characteristics of 2H per ASTM D3363--92A a nd cross--hat ch adhesion of 4B--5B per
ASTM D3359--93.
f. Impact resistance shall be up to 160 in.--lb (ASTM D2794 --93).
g. Humidity and water immersion resistance shall be up to minimum 1000 and 250 hours respectively (ASTM
D2247--92 a nd ASTM D870--92).
h. Corrosion durability shall be confirmed through testing to be no less than 1000 hours salt spray per ASTM
B117--90.
5. Standard All Aluminum Novation Coils:
a. Standard condenser coils shall have all aluminum NOVATION Heat Exchanger Technology design consist-
ing of a luminum multi port flat tube design and aluminum fin. Coils shall be a furnace brazed design and
conta in epoxy li ned shrink wrap on all aluminum to copper connec tions.
b. Condenser coils shall be leak tested to 150 psig, pressure teste d to 650 psig, and qualified to UL 1995 burst
test a t 1980 psig.
6. Optional E --coated aluminum--fin, aluminum tube condenser coils:
a. Shall have a flexible epoxy polymer coat ing uniformly applie d to all coil e xternal surface areas without
material bridging betwe en fins or louvers.
b. Coating process shall ensure comple te coil encapsulation, incl uding all exposed fin edges.
c. E--coat thickness of 0.8 to 1.2 mil with top coat having a uni form dry film thickne ss from 1.0 to 2.0 mil on
all external coil surface areas, including fin edges, shall be provided.
d. Shall have superior ha rdness characteristic s of 2H per ASTM D3363--00 and cross--hatch adhesion of
4B--5B per ASTM D3359--02.
e. Shall have superior impac t resistance with no cracking, chipping or peeling per NSF/ANSI 51--2002 Method
10.2.
23 81 19.13.K. Refrigera nt Components
1. Refrige rant circuit shall include the following control, safety, and maintenance fea tures:
a. Fixed orifice metering system shall prevent mal--distribution of two-- phase refrigerant by including multiple
fixed orifice devices in each refrigeration circuit. Each orifice is to be optimized to the coil circuit it serves.
b. Refrigerant filter drier -- Solid core design.
c. Service gauge connections on suction and di scharge lines.
d. Pressure gauge access through a specially designed access port i n the top panel of the unit.
2. There shall be gauge line access port in the skin of the rooftop, covered by a black, removable plug.
a. The plug shall be easy to remove and replace.
b. When the plug is removed, the gauge access port shall enable maintenance personnel to route their pressure
gauge l ines.
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