FAQWe collected the most frequently asked questions below, enjoy!!

  • What is a Pro-Flex® Flexible Gas Piping System?

    Pro-Flex® is a corrugated stainless steel tubing [CSST] piping system. Pro-Flex CSST offers a flexible alternative to rigid pipe systems that are commonly used to distribute fuel gases [natural and propane gas] throughout a structure. Pro-Flex, LLC offers both the traditional yellow jacketed Pro-Flex CSST and Flak Jacket™ Arc- Resistant CSST tubing. With today’s modern technology, flexible piping systems provide a time and cost saving way to offer your customers clean-burning, reliable gas appliances. Pro-Flex’s flexible gas piping systems are an ideal method to run gas piping in new construction [including single family, multi-family, commercial, and industrial structures]; or renovations, additions, and gas appliance additions or conversions.

  • Why should I use Pro-Flex® rather than conventional rigid [black iron or galvanized] pipe?

    • Pro-Flex flexible gas piping systems can save up to 75% of the installation time required for a conventional rigid pipe system.

    • The potential number of leak points is greatly reduced as a CSST system utilizes fewer joints/ fittings per run.

    • No specialized cutting & threading equipment is required. CSST is cut using a standard tube cutter. In addition, there is no dirty/hazardous waste [cutting oil] to deal with.

    • Pro-Flex flexible gas piping systems are extremely lightweight and easy to transport as well as requiring less storage or staging space.

  • How are Pro-Flex CSST and Flak Jacket™ Arc-Resistant CSST different from other CSST systems?

    • Pro-Flex Fittings are easy to install/assemble. No special tools are required. No flaring is required. Pro-Flex’s patented sealing system eliminates the most common complaint of other CSST systems- leaking fittings- it doesn’t rely on the quality of the cut edge of the CSST to create the seal.

    • Pro-Flex offers the simplest dual-sealed CSST fittings to assemble. There is a reason that we haven’t changed our fitting design since its inception—IT WORKS! The fittings have been tested for long life while withstanding extreme heat and cold.

    • Pro-Flex CSST fittings and components are reusable.

    • Pro-Flex CSST and Flak Jacket™ Arc-Resistant CSST are annealed to give the pipe better flexibility without altering its strength. In addition, with post forming annealing the tubing doesn’t dangerously “spring free” when unpackaged and stays in place when bent.

    • Pro-Flex CSST and Flak Jacket™ Arc-Resistant CSST are 100% leak tested in the factory.

    • Pro-Flex CSST and Flak Jacket™ Arc-Resistant CSST coils are packaged for easy dispensing.

    Download Installation Guide

  • Do you need special tools to install Pro-Flex flexible gas piping systems?

    No special tools are required. A tube cutter [such as the Pro-Flex Tubing Cutter PFTC-01P] and a pair of wrenches are the basic tool requirements.

    Download Fitting Assembly Instructions

  • Are Pro-Flex flexible gas piping systems approved for use in my area?

    Pro-Flex flexible gas piping systems are approved for use in the US and Canada. Please consult your local jurisdiction to confirm the acceptance of flexible gas piping as local code requirements can be more restrictive than state or national model codes.

  • Is this product certified by CSA, UL, or any other listing agency?

    This product is listed to ANSI LC 1-2016 • CSA 6.26- 2016 [CSA certificate of compliance 1174673 and IAPMO Research and Testing File No. 3669]. It must be installed in accordance with local codes, or, in the absence of local codes, in accordance with National Fuel Gas Code, ANSI Z223.1/NFPA 54; Natural Gas and Propane Installation Code, CSA B149.1 & B149.2 in Canada; the International Fuel Gas Code; the Federal Manufactured Home Construction and Safety Standard, 24 CFR Part 3280; the Manufactured Housing Construction and Safety Standards, ICC/ANSI 2.0; or the Standard on Manufactured Housing, NFPA 501; as applicable. UL approval is not required.

  • Do Pro-Flex fittings work with other brands of CSST tubing? / Will Pro-Flex tubing work other brands of CSST fittings?

    All Pro-Flex mechanical joint fittings terminate in a standard NPT [male or female] pipe threads to allow for transition between Pro-Flex CSST or Flak Jacket Arc Resistant CSST and: rigid pipe, couplings, unions, valves, etc. Interconnection of tubing and fittings with other CSST brands is prohibited!

  • What is the maximum GAS pressure that Pro-Flex’s flexible gas piping systems are approved to operate at?

    Pro-Flex CSST and Flak Jacket Arc Resistant CSST are approved for use in gas piping systems that operate at a MAXIMUM of 5psi.

  • Can Pro-Flex CSST and Flak Jacket Arc-Resistant CSST be buried?

    Flexible gas piping systems [Pro-Flex CSST and Flak Jacket Arc Resistant CSST] may be used underground when routed in a water-tight, non-metallic conduit – no Pro-Flex fittings are allowed in the conduit. For details, see section 4.3 pages 20-21 of Pro-Flex, LLC Flexible Gas Piping Systems – Pro-Flex CSST & Flak Jacket Arc-Resistant CSST – Installation / Training Guide.

    Download Installation / Training Guide

  • How do I become a Pro-Flex / Flak Jacket Qualified Installer?

    Pro-Flex® CSST and Flak JacketTM Arc-Resistant CSST must be installed by a qualified installer who meets the following criteria:

    1. Installer must meet all qualifications required by the state and/or local administrative authority [AHJ] administering the provisions of the code where the gas piping is installed.

    2. An installer must also be qualified in the use of Pro-Flex® and Flak JacketTM CSST. Qualification for Pro-Flex, LLC's CSST systems can be completed by reading the Pro-Flex®, LLC's Flexible Gas Piping System Installation/Training Guide and registering with Pro-Flex, LLC to obtain a Qualified Installer Card by either mailing in the registration card from the back of the guide or registering online.

    Download Installation / Training Guide    Register to Become a Qualified Installer Here

  • Are gas piping systems that contain at least one segment of Pro-Flex CSST or Flak Jacket Arc Resistant CSST required
    to be bonded to the structure’s electrical grounding system?

    Please click below and read the ICC 2015 Code Notes: Bonding of Corrugated Stainless Steel Tubing [CSST] Gas Piping System. If after reading this selection, you have additional questions please email those inquiries to ProFlexTech@Pro-FlexCSST.com.

    Download ICC 2015 Code Notes

  • What is the Pro-Flex Privacy Policy?


    Pro-Flex Online Privacy Policy

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    We are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects personally identifiable information. This privacy statement applies solely to information collected by this website.

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    If a user wishes to subscribe to be a registered user, we ask for contact information such as name and e-mail address. This info is only requested for registered users.