Castair 3/4" Copper Tubing (Sold by the Foot) CT75
Castair's 3/4" copper tubing is the largest in their copper tubing line, sold by the linear foot for discharge connections, large-bore compressor plumbing, and high-CFM system connections. At $15.40 per foot, this is the discharge tube material for larger two-stage and duplex reciprocating compressors and the correct copper size for Castair's 3/4" in-tank check valves and aftercooler connections. If your system calls for 3/4" copper, CT75 is the factory-correct material.
Where 3/4" Copper Tubing Is Used
- Discharge tubes on large compressors: Two-stage commercial and industrial reciprocating compressors typically use 3/4" copper discharge tubes from head to tank
- Aftercooler connections: Castair's BGAC and FSAC aftercooler series use 3/4" and larger connections — 3/4" copper feeds these units
- In-tank check valve connections: Castair's 3/4" compression check valves (CTD3434, CTD3410) use 3/4" compression tube fitting inlets — this tubing connects directly
- Duplex compressor installations: Plumbing connecting dual compressor units to the common manifold or tank
- Large-bore supply mains: Short runs of 3/4" main line where semi-rigid copper is preferred over threaded pipe
Technical Considerations
- Temperature handling: Copper is rated for continuous use at compressor discharge temperatures (200-350°F). The discharge side of any reciprocating compressor runs hot — copper or steel only, not flexible hose or nylon
- Companion fittings: Castair makes 3/4" compression nut and sleeve (CNS34), compression adaptor (CA3434), compression elbow (CE3434), and pre-assembled 3/4" discharge tube with fittings (DT34)
- Vibration isolation: Always form a coil or offset bend where 3/4" copper connects to a vibrating compressor head — straight rigid connections fatigue at fittings over time
Ordering Information
- Sold by the foot — specify footage when ordering
- Part Number: CT75
- Price: $15.40 per foot
Castair Copper Tubing Lineup
- CT25 — 1/4" copper tubing, $7.70/ft — control, pilot, and gauge lines
- CT50 — 1/2" copper tubing, $10.01/ft — standard discharge tube size for smaller compressors
- CT58 — 5/8" copper tubing, $13.09/ft — larger discharge and inter-stage connections
- CT75 — 3/4" copper tubing, $15.40/ft (this listing) — large-bore discharge and high-CFM connections
Technical Specifications
- Part Number: CT75
- Manufacturer: Castair (Spicer, Minnesota)
- Material: Copper tubing
- Size: 3/4"
- Sold: By the linear foot
- Price: $15.40 per foot
- Application: Discharge tubes, aftercooler connections, large-bore compressor plumbing
Why Buy From Air Compressor Factory Direct?
We stock the full Castair tubing and fittings line. If you're plumbing a new system or replacing discharge tubing, we can confirm the correct tube size and help you identify the right compression fittings to pair with it. No guessing on sizes.
- Free shipping on qualifying orders to the lower 48
- Free tech support — call with sizing questions before you order
- Full manufacturer warranty on all Castair products
Call 866-217-0063 for quick answers and help!
