Pro-Flex
Pro-Flex CSST Union Fittings
- Availability:
- Usually Ships in 5-7 Business Days
- Weight:
- 0.00 LBS
Description
Pro-Flex CSST Union
Pro-Flex CSST Unions provide an inline connection for joining compatible sections of Pro-Flex corrugated stainless steel gas tubing. Designed as part of the Pro-Flex fitting system, these unions create a convenient connection point between CSST runs while maintaining a compact fitting configuration.
Available for 1/2", 3/4", 1", and 1-1/4" CSST, the union lineup allows the fitting size to be matched directly to the tubing used in the installation. The Pro-Flex product guide lists unions among its CSST fitting options and identifies 1/2", 3/4", and 1" models.
Product Highlights
- Inline union fitting for Pro-Flex CSST gas piping
- Designed to connect compatible CSST tubing sections
- Available in 1/2", 3/4", 1", and 1-1/4" sizes
- Compact fitting configuration for gas piping installations
- Useful for extending or joining CSST runs
- Part of the Pro-Flex CSST fitting system
- Suitable for properly designed natural-gas and propane piping systems
- Available as Pro-Flex part numbers PFUF-1212, PFUF-3406, PFUF-0106, and PFUF-0114
Available Models
| Part Number | Tube Size | Description |
|---|---|---|
| PFUF-1212 | 1/2" | Union |
| PFUF-3406 | 3/4" | Union |
| PFUF-0106 | 1" | Union |
| PFUF-0114 | 1-1/4" | Union |
Technical Specifications
| Manufacturer | Pro-Flex |
|---|---|
| Product Type | CSST Union |
| Compatible Piping System | Pro-Flex CSST |
| Available Sizes | 1/2", 3/4", 1", and 1-1/4" |
| PFUF-1212 Size | 1/2" |
| PFUF-3406 Size | 3/4" |
| PFUF-0106 Size | 1" |
| PFUF-0114 Size | 1-1/4" |
| Configuration | Inline Union |
| Primary Application | Joining Compatible Pro-Flex CSST Runs |
What Is a Pro-Flex CSST Union?
A CSST union is an inline fitting used to connect two compatible sections of corrugated stainless steel gas tubing. It creates a defined connection point between tubing runs without changing the nominal tubing size.
Pro-Flex unions are sized to correspond with the CSST used in the installation. Selecting the correct union requires matching the fitting to the tubing size and confirming compatibility with the applicable Pro-Flex gas piping system.
Union fittings can be useful where separate CSST runs need to be joined as part of an approved gas piping layout.
Why Use a CSST Union?
Inline Connection
- Joins compatible sections of CSST tubing
- Maintains the same nominal tubing size through the connection
- Provides a defined fitting point within the piping run
- Useful when connecting separate lengths of tubing
- Available across several common Pro-Flex CSST sizes
Pro-Flex System Fitting
- Designed as part of the Pro-Flex CSST fitting system
- Matches common Pro-Flex tubing sizes
- Compact configuration for gas piping layouts
- Suitable for properly designed CSST installations
- Provides an alternative to changing piping systems at an inline connection
Available Union Sizes
PFUF-1212 – 1/2"
The PFUF-1212 is a 1/2" Pro-Flex union designed for compatible 1/2" CSST gas piping installations.
PFUF-3406 – 3/4"
The PFUF-3406 is a 3/4" Pro-Flex union designed for compatible 3/4" CSST gas piping installations.
PFUF-0106 – 1"
The PFUF-0106 is a 1" Pro-Flex union designed for compatible 1" CSST gas piping installations.
PFUF-0114 – 1-1/4"
The PFUF-0114 is a 1-1/4" Pro-Flex union designed for compatible 1-1/4" CSST gas piping installations.
Common Applications
CSST Gas Piping
- Joining two compatible CSST tubing runs
- Extending an existing CSST run where permitted
- Residential gas piping systems
- Light-commercial gas piping installations
- Mechanical gas distribution systems
Gas Equipment Distribution
- Gas appliance supply piping
- Water-heater gas piping
- Furnace and boiler gas distribution
- Fireplace and hearth gas piping
- Other properly designed natural-gas or propane systems
Pro-Flex CSST System Compatibility
Pro-Flex offers a corrugated stainless steel tubing system for natural-gas and propane applications. The manufacturer's product guide identifies unions as part of its CSST fitting lineup and states that the fitting system is intended for use with both Pro-Flex Yellow CSST and Flak Jacket arc-resistant CSST. :contentReference[oaicite:1]{index=1}
Always verify that the tubing, union, and other components selected for a project are compatible with the specific Pro-Flex system and installation requirements.
Choosing the Correct Union
| Part Number | CSST Size | Use When Connecting |
|---|---|---|
| PFUF-1212 | 1/2" | Compatible 1/2" Pro-Flex CSST |
| PFUF-3406 | 3/4" | Compatible 3/4" Pro-Flex CSST |
| PFUF-0106 | 1" | Compatible 1" Pro-Flex CSST |
| PFUF-0114 | 1-1/4" | Compatible 1-1/4" Pro-Flex CSST |
Installation Considerations
- Select the union that matches the nominal Pro-Flex CSST tube size.
- Verify tubing and fitting compatibility before installation.
- Prepare and connect CSST according to current Pro-Flex installation instructions.
- Do not substitute a different-size union for the tubing being connected.
- Protect exposed CSST and fittings where required by the installation.
- Support gas piping in accordance with manufacturer instructions and applicable codes.
- Leak-test completed connections according to applicable requirements.
- Confirm that the complete gas piping system is properly sized for the connected load.
- Follow applicable fuel-gas codes and local installation requirements.
- Installation should be completed by qualified gas-piping personnel.
Pro-Flex Fitting Installation
Pro-Flex describes its CSST fitting installation as a three-step process involving removal of the tubing jacket, positioning of the retainer, slide ring and O-ring, and tightening of the fitting. The manufacturer specifies that installers should follow the applicable Pro-Flex installation procedure for the fitting and tubing being used.
Always refer to current Pro-Flex installation documentation for the complete fitting assembly procedure, required tools, inspection steps, and gas-system testing requirements.
Need Help Selecting a Pro-Flex Union?
Our industrial PVF specialists can help review your Pro-Flex CSST size, piping configuration, fitting requirements, and application before you order.
Frequently Asked Questions
What is a Pro-Flex union used for?
A Pro-Flex union is used as an inline fitting to join two compatible sections of Pro-Flex CSST gas tubing.
What union sizes are available?
The listed models are available in 1/2", 3/4", 1", and 1-1/4" sizes.
What size is PFUF-1212?
PFUF-1212 is the 1/2" Pro-Flex union.
What size is PFUF-3406?
PFUF-3406 is the 3/4" Pro-Flex union.
What size is PFUF-0106?
PFUF-0106 is the 1" Pro-Flex union.
What size is PFUF-0114?
PFUF-0114 is the 1-1/4" Pro-Flex union.
Does a union reduce the tubing size?
No. These union models are intended as same-size inline connections. Select the union that matches the nominal CSST size being connected.
Can a Pro-Flex union be used to extend a CSST run?
A union provides a connection between compatible sections of CSST and may be incorporated into a piping run where permitted by the system design, manufacturer instructions, and applicable codes.
Can these fittings be used with natural gas or propane?
Pro-Flex CSST is designed for natural-gas and propane piping systems. Verify the complete installation and all selected components for the specific application.
Who should install Pro-Flex CSST unions?
CSST gas piping and fittings should be installed by qualified personnel according to current Pro-Flex installation instructions and applicable fuel-gas codes.
Important Ordering Notes
- PFUF-1212 is a 1/2" union.
- PFUF-3406 is a 3/4" union.
- PFUF-0106 is a 1" union.
- PFUF-0114 is a 1-1/4" union.
- Select the union that matches the nominal CSST size being connected.
- Confirm compatibility with the applicable Pro-Flex CSST system before ordering.
- Confirm that the fitting configuration is permitted for the intended installation location.
- Follow current Pro-Flex installation instructions when assembling CSST fittings.
- Follow applicable fuel-gas codes and local installation requirements.
- Installation should be completed by qualified gas-piping personnel.
