Secondary surface (fins) are of the plate-fin design using aluminum or copper, with die-formed collars. The fin design is to be flat, waffle, or sinewave in a staggered tube pattern to meet performance requirements. Collars will hold fin spacing at specified density and cover the entire tube surface. Aluminum properties are to be Alloy 1100 per ASTM B209, with O (soft) temper; copper is to be Alloy 11000 per ASTM B152-06 with soft (anneal) temper. Fins are to be free of oils and oxidations.
Tubes and return bends shall be constructed from seamless UNS C12200 copper conforming to ASTM B75 and ASTM B743. Properties shall be O50 light annealed, with a maximum grain size of 0.040mm. Seamless tubes are to be mechanically expanded into plate fins for maximum heat transfer.
Headers are constructed of seamless UNS C12200, Type L copper material sized to match specified connection size. Headers are to have finished integral spin-closed ends designed to withstand test pressure. 1/4” vents and drains are provided for al fluid coils unless specified otherwise.
Connection material can be copper, schedule 40 steel, or red brass pipe. The type of connection is to be sweat type, MPT or FPT, grooved, or flanged as required.
Coil casing material shall be 16-gauge, G90 galvanized steel. Heavier gauge and optional material casings are available as required to meet specification. Intermediate tube supports are to be provided on all coils 50” and longer in fin length. Coil casings on top and bottom of coils are to have double-flanged construction, allowing for vertical stacking of coils.
Coils comprised of round tubes shall be tested at 550 PSIG using dry nitrogen while submerged underwater. Dual-operator verification determines that all coils are leak-free. Sectional and cleanable coils designed with removable sections shall be leak tested at two times the recommended operating pressure, or 150 PSIG. Fluid coils shall be designed for 390+ PSIG water operating pressure (based on the tube and header O.D.) and guaranteed up to 200° F working temperature.
All water coils designed with 1/2” or 5/8” tubes are to be AHRI performance certified and bear the AHRI symbol. Coils outside the scope of the AHRI’s standard rating conditions or the manufacturer’s certification program will be acceptable since the manufacturer is a current member of the AHRI coil certification program, and coils will be rated in accordance with AHRI Standard 410.
FLUID COILS (HW & CW)
Standard/Base in Bold Below
Tube O.D. | Tube Thick | Optional Tube | Fin Thick. | Optional Fin |
3/8″ | .014 | .016 .022 | .006 | .0075 |
1/2″ | .016 | .025 | .006 | .0075 .010 |
5/8″ | .020 | .025 .035 .049 | .006 | .0075 .010 |
FLUID COILS (HW & CW)
Standard / Optional
Fin Material | Aluminum | Optional -Copper; Stainless Steel |
Casing Material | 16 gauge Galv. Steel | Optional - 12, 14, and 18 Gauge Galv. Steel • 12, 14, and 16 Gauge 304 & 316 Stainless Steel • 14 Gauge Aluminum |
Tube Material | Copper | Optional - Stainless Steel, Cupro Nickel, Carbon Steel |
Connection Material | Copper | Optional - Steel & Red Brass |
Header Material | Copper | Optional - Stainless Steel, Cupro Nickel, Carbon Steel |
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