Secondary surface (fins) are of the plate-fin design using aluminum or copper, with die-formed collars. The fin design for 5/8” & 1/2” O.D. tubes is to be flat, waffle, or sinewave in a staggered tube pattern to meet performance requirements. The fin design for 3/8” O.D. tubes is to be flat, louvered, or sinewave in a staggered tube pattern to meet performance requirements. Collars will hold fin spacing at the 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 to be 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.
Condenser coils shall be designed with copper sweat connections and shall be shipped with caps on the connections.
Coil casing material shall be 16-gauge, G90 galvanized steel. Heavier gauge and optional material casings are available as required to meet specifications. Coils designed for hot-gas applications shall have oversized tube sheet holes for hot gas feeds to allow for free expansion and contraction of tubes during operation. Intermediate tube supports are to be provided on all coils 50” and longer fin length. Coil casings on top and bottom of coils are to have double-flanged construction, allowing for vertical stacking of coils.
Coils shall be tested at 550 PSIG using dry nitrogen, submerged underwater. Dual-operator verification shall determine that all coils are leak-free. Coils shall be shipped with nitrogen charge to verify leak-free integrity and to prevent moisture migration into the coil.
Coils shall be UL recognized as Refrigerant Containing Component. Coils that are to be used with refrigerant R-410A shall have undergone cycle testing and shall be safely listed with 750 PSIG rating.
Standard/Base in Bold Below
|3/8″||.014||.016 & .022||.006||.0075|
Standard / Optional
|Fin Material||Aluminum||Optional - Copper|
|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|
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