Mueller Streamline 3/4" x 50' Soft Copper Refrigeration Coil, American Made, RTB3450
For HVAC contractors who want domestic copper on the suction side, the Mueller Streamline RTB3450 delivers a full 50 feet of 3/4" OD dead-soft refrigeration tube made in the USA. The 3/4" size is a workhorse suction line diameter on many smaller residential split systems and commercial refrigeration circuits. A continuous coil lets you route the vapor line from the air handler or evaporator to the condensing unit with fewer joints. Mueller supplies it bright, dried and dehydrated, then shrink-wraps and cartons each coil to protect the tube until it's installed.
Is a 3/4" Copper Coil the Right Size?
The suction line returns low-pressure refrigerant vapor to the compressor, so it's sized larger than the liquid line. A suction line that's too small causes excess pressure drop and lost capacity. One that's too large can make oil return to the compressor harder. Many smaller residential split systems specify a 3/4" OD suction line, but the final call belongs to the equipment manufacturer's installation instructions.
Equipment tonnage, total equivalent line length, vertical rise between the indoor and outdoor units, and refrigerant type can all push the recommended suction size up or down. If your run is unusually long or has significant lift, check the long-line guidelines before choosing 3/4".
Ideal for: Suction lines on smaller residential split AC and heat pump systems, walk-in cooler refrigeration piping, system change-outs and suction line replacement.
Need a larger diameter? Step up to the Mueller Streamline 7/8" x 50' Copper Line, RTB7850 when the equipment's piping tables call for a larger suction line.
Recommended line-size applications are general guidelines only. Correct suction line sizing depends on the equipment manufacturer's piping tables, system capacity, line length, vertical lift and refrigerant type. Request free sizing assistance, contact Budget Heating, or call 813-885-7999.
What's Included
| Brand | Mueller Streamline |
|---|---|
| Model | RTB3450 |
| Product Type | Soft Copper Refrigeration Tube Coil |
| Outside Diameter | 3/4" OD |
| Coil Length | 50 Feet |
| Temper | Dead Soft |
| Tube Condition | Bright, Thoroughly Dried / Dehydrated |
| Country of Origin | Made in the USA |
The RTB3450 ships as one 50-foot length of 3/4" soft copper, packed in its own carton. A single uninterrupted suction line means fewer couplings to braze and fewer places for leaks. Pair it with a 3/8" liquid line, plus insulation such as 3/4" x 3/4" Rubatex insulation tubing or UV-resistant K-Flex Titan 3/4" insulation for outdoor runs, and you have a complete field-built line set.
Condensing Unit & Evaporator Features
Mueller Streamline RTB3450 Copper Quality
- Domestic copper made in the USA by Mueller Streamline
- Dead-soft temper bends smoothly around framing and obstacles
- Bright, clean tube interior
- Dried and dehydrated before packaging
- Individually shrink-wrapped and boxed coil
- One 50' continuous length for fewer brazed joints
- 3/4" OD suction line diameter
- Trusted Streamline brand used by HVAC/R contractors nationwide
Jobsite Advantages of the 3/4" Coil
- Suction lines on many smaller residential split systems
- Refrigeration piping for walk-in coolers and reach-in equipment
- Replacing undersized or damaged suction lines during change-outs
- Building custom-length line sets on site
- Insulate with matching copper fittings, insulation and accessories
- Clean out existing lines first with the Easy One-Step Ultra Flush Kit
- Pairs with the 3/8" RTB3850 coil for the liquid side
- Browse more copper lines and kits for other sizes
Specifications & Manuals
Use the Mueller Streamline submittal, lead-free compliance letter and copper standards document for job submittals, inspector questions and specification review.
Frequently Asked Questions
Is 3/4" copper used for the suction line or the liquid line?
In split-system air conditioning and heat pumps, 3/4" OD copper is normally used on the suction (vapor) side. The liquid line is usually smaller, commonly 3/8". Confirm sizes against the equipment manufacturer's piping tables.
How is the 3/4" RTB3450 different from the 3/8" RTB3850?
Both are 50' Mueller Streamline soft copper coils made in the USA. The RTB3450 has twice the outside diameter, which suits it to low-pressure suction vapor. The 3/8" RTB3850 is sized for liquid lines and oil lines.
Does the RTB3450 come with insulation?
No. The RTB3450 is copper refrigeration tube only. Suction lines are normally insulated, so pair this coil with 3/4" ID insulation tubing, such as Rubatex or UV-resistant K-Flex Titan for outdoor exposure.
Can I build my own line set with this coil?
Yes. Many contractors build field line sets by pairing a 3/4" suction coil with a 3/8" liquid coil and the correct insulation. This lets you match each install's exact routing instead of working around a pre-made line set.
Why choose American-made Mueller copper over imported tubing?
Mueller Streamline produces its ACR copper tube in the USA and backs it with published submittals, standards documents and lead-free compliance information. That paperwork is useful for commercial submittals and for buyers who specify domestic material.
Is 3/4" soft copper also used in commercial refrigeration?
Yes. Refrigeration installers use 3/4" soft copper on many walk-in cooler and reach-in refrigeration systems. Follow the condensing unit and evaporator manufacturers' line-sizing charts for each system.
Mueller Streamline Copper SubmittalMueller Streamline Lead-Free ComplianceMueller Streamline Copper Standards
