We offer direct expansion (DX) evaporator coils for air conditioning, dehumidification, and refrigeration applications, for use with a variety of refrigerants
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DIRECT EXPANSION COIL - TYPE DX
Primary Surface
Round seamless copper tubes are mechanically expanded into the fin collars of the secondary surface. The mechanical expansion provides a permanent metal-to-metal bond for efficient heat transfer. Tubes are staggered in the direction of airflow and only RETURN BENDS are used to ensure NO reduction in tube wall thickness in the bend radius associated with hairpin tubes.
Secondary Surface
Corrugated aluminum or copper plate-type fin that is die-formed. Fin collars are full-drawn to provide accurate control of fin spacing and maximum contact with tubes.
Headers
Seamless copper with die-formed holes that provide a parallel surface to the coil tube for strong brazing joints.
Connections
Interchangeable nozzle-type refrigerant distributors are brass and suction connections are copper sweat. Standard coil has one distributor for one compressor circuit. An INTERTWINED coil has two distributors that provide full face control using two compressor circuits. A FACE SPLIT coil has two or more distributors for multiple compressor circuits.
Casing
Die-formed flanges with stacking flanges on top and bottom. Intermediate tube supports are supplied on coils over 44” fin length with an additional support every 42”.
Circuiting
Coil circuiting options include full face (std.), intertwined, horizontal (face) split, and face split / intertwined.
Testing and Performance
All coil assemblies are leak tested under water with nitrogen at 315 PSIG.
COIL OPTIONS
Direct Expansion Coil – Type DX
Fin Height: 6” to 60”
Fin Length: 20.25” to 157”
Fin Spacing:
1/2” – 8 to 14 fins per inch
5/8” – 6 to 14 fins per inch
Fin Thickness ALUMINUM:
1/2” – 0.006”
5/8” – 0.008” or 0.010”
Fin Thickness COPPER:
1/2” – 0.006”
5/8” – 0.006” or 0.008” or 0.010”
Tube O.D.Tube Thickness:
1/2” – 0.017” or 0.025”
5/8” – 0.020” or 0.025”
Tube Spacing Face x Row:
1/2” – 1.25”x1.083”
5/8” – 1.50”x1.299”
Casing:
16 or 14 GA Galvanized Steel
304, 316 Stainless Steel
Max. Std. Operating Conditions: 250 PSIG