CSST Flexible Gas Pipe System Design and Installation Manual
Suggested Tools for Installation of HOME-FLEX® Use to cut HOME-FLEX® tubing to desired length. Tubing Cutter Note: Turn knob slowly while rotating around the tubing to avoid bending or crushing the tubing. Use to remove yellow protective jacket at tubing end where the fitting is to be installed. Utility Knife Use to the retainer ring in place on first corrugation (or valley) of the HOME-FLEX® tubing. Slip-joint (or similar) Pliers Use in fitting assembly to fuse the CSST and NPT ends of the fitting.
Table of Contents Chapter 1: Introduction 1.1 User Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Limitations of Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.3 Applicable Codes and Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Chapter 2: Description of System Components 2.1 Tubing . . . . . . . . . . . . . . . . .
Through-Wall Penetration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 4.5 Meter connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Connection by Special Termination Fitting . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Direct Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 4.6 Appliance connections . . . . . . . . . . . . . . .
Chapter 1: Introduction 1.1 User Warnings HOME-FLEX® Corrugated Stainless Steel Tubing (CSST) flexible gas piping material must be installed by a Qualified Installer who has been certified in the use of the HOME-FLEX® or VPC Alpha-FLEX™ gas piping systems.
Introduction Exposure to high voltage electricity may cause damage to CSST systems. Strict adherence to Section 4.10, “Electrical Bonding” (p. 34), will mitigate potential damage. Wear gloves, eye protection, and suitable protective clothing when working with HOME-FLEX® CSST and fittings. WARNING! If installed improperly, fire, explosion or asphyxiation may result. Installation instructions and applicable local codes must be strictly followed.
Applicable Codes and Standards The inspection, testing and purging of the installation shall be performed using the procedures specified in Part 4, General, of the National Fuel Gas Code (ANSI Z223.1/NFPA 54), and/ or the Natural Gas and Propane Installation Code (CSA B149.1), the International Fuel Gas Code, the Uniform Plumbing Code, or in accordance with the requirements of the applicable local codes. The installed gas piping system shall not exhibit any loss of pressure during the field pressure test.
Chapter 2: Description of System Components 2.1 Tubing The HOME-FLEX® fuel gas piping system employs corrugated, flexible, semi-rigid stainless steel tubing with brass attachment fittings terminating in NPT pipe fittings for integration into traditional rigid black pipe systems or direct connection to gas systems. Tubing is available in sizes of ½", ¾", and 1". HOME-FLEX® tubing is jacketed with a yellow polyethylene cover clearly marked with gas pressure rating, and EHD* (Equivalent Hydraulic Diameter).
2.2 Fittings HOME-FLEX® fittings are available for ½", ¾", and 1" HOME-FLEX® tubing and allow for easy connection to gas systems and accessories using standard NPT threads. (See Figure 2.1) In addition to standard NPT adapter fittings, the following are also available: Tee fittings to accommodate branch lines in tubing runs, reducer tees to integrate with different sized tubing runs, and special termination flanges for convenient gas appliance connections. Part No.
Description of System Components 2.4 Pressure Regulators Pressure regulators are used in elevated pressure system installations (over 14 inches water column, or ½ PSI) to reduce pressure to standard low pressure required for appliances. Part No. Description Maxitrol 325-3L ½" NPT 7-11" w.c. Gas Line Pressure Regulator (250,000 Btu/hr max) Maxitrol 325-5AL ¾" NPT 7-11" w.c. Gas Line Pressure Regulator (425,000 Btu/hr max) 2.
Bonding Clamps Quick-connect devices provide a safe and easy way to make connections to moveable outdoor gas appliances like barbecues and space heaters. Quick-connect devices used with HOME-FLEX® gas piping systems must conform to ANSI Z21.15, CGA 9.1, 9.2, 6.9 and AGA/ CGA 7-90/CR94-001. A shut-off valve should be installed upstream of the quick-connect device and remain in the off position when the quick-connect device is not in use. All installations and devices must conform with local codes.
Description of System Components 2.10 Replacement Parts HOME-FLEX® fittings require a retainer ring, a non-metallic gasket, and an o-ring for proper assembly (see Figure 2.1 on page 4). Should any of these components be damaged or misplaced, packs of replacement rings are available. Part No.
Chapter 3: Sizing and Configurations 3.1 Configuration Before routing HOME-FLEX® tubing, it is advisable to prepare a sketch from the building plans showing the locations of appliances to be serviced by the gas line, the load demands of each appliance, the point of delivery (location of gas meter or second stage liquid petroleum (LP) regulator), system pressure, and possible piping routes and lengths.
• For natural gas with a specific gravity of 0.60, one cubic foot per hour (1 CFH) is approximately 1,000 BTUH. • For LP gas with a specific gravity of 1.52, one cubic foot per hour (1 CFH) is approximately 2,500 BTUH. For any given system and its load requirements, there are several piping system designs available to the installer using HOME-FLEX® tubing. The sections below will outline several demand scenarios and the different system options open to the installer.
Sizing Methods and Examples routed to each appliance location. Manifold stations are located as close as possible to the appliance(s) with the greatest load. Parallel layouts are most commonly used in ¼ to ½ PSI systems. Dual Pressure Systems Elevated pressure systems generally have a main line from the gas supply to one or more gas pressure regulators and then a manifold with "home runs" to appliances. These runs may branch off through use of a tee, if gas loads permit.
Sizing and Configurations inlet pressure (recommended 5 inches w.c. for natural gas and 10.5 inches w.c. for propane) from the gas source pressure (gas meter for natural gas or the secondary regulator for LP). Low pressure series systems are sized using the "longest length method" (also known as the "branch length method") in the same manner as low pressure black steel pipe systems. Tables from the National Fuel Gas Code (NFPA 54) are used to calculate the sizing.
Sizing Methods and Examples Step 2 Size Section B: Determine the length of the run from the meter to the range oven and the load delivered. • The length from the meter to the range oven is 20 feet (A + B), and the load is 40 CFH (40,000 BTUH divided by 1000 CF per BTU). • Consulting Table 7.1, we see that for a 20-foot run, ½" tubing will supply up to 51 CFH. The correct size tubing for section B is ½".
Sizing and Configurations Step 4 Size Section D: Determine the length from the meter to the water heater. • A + D = 32 feet, and the load of the water heater is 25,000 BTUH = 25 CFH. • Table 7.4 shows that ½" tubing has a total load capacity of 116 CFH at 40 feet, so ½" tubing is the correct size. Step 5 Size Section E: Determine the length from the Range oven to the Furnace. • A + E= 30 feet and the load of the furnace is 40,000 BTUH = 40 CFH. • Table 7.
Sizing Methods and Examples Example 4: Medium Pressure Parallel Arrangement with a Series Branch This installation has a barbecue installed near the water heater. Given the number of appliances, a parallel arrangement was selected for the system, with a single run supplying the barbecue and the water heater in series. Med Pressure (12-14" w.c.) 1/2 PSI Gas Meter 30,000 BTUH Dryer Range Oven 40,000 BTUH D Furnace C B 60,000 BTUH E A BBQ F 50,000 BTUH Water Heater G 25,000 BTUH Figure 3.
Sizing and Configurations Step 6 Size Section F: Determine the total length and load. • The BBQ load is 50 CFH and the length is 60 feet (A + E + F). • ½" Tubing has a maximum capacity of 96 CFH at 60 feet so ½" is the correct size. Step 7 Size Section G: Determine the total length and load. • The water heater load is 25 CFH and the length is 50 feet (A + E + G). • ½" Tubing has a maximum capacity of 104 CFH at 50 feet, so ½" is the correct size.
Sizing Methods and Examples 400 CFH, which at 70 feet can be supplied by 1¼" pipe with a maximum capacity of 490 CFH. 1¼" pipe is the correct size for section A2. • To size section A3, we can reduce the load by another 190 CFH to 210 CFH for the remaining heater and the water heater. At 70-feet, 1" pipe can supply a maximum of 240 CFH, which is sufficient for the run. 1" pipe is the correct size. • To size section A4, the load is reduced to just the 60 CFH of the water heater.
Chapter 4: Installation Practices 4.1 General Practices HOME-FLEX® CSST flexible gas piping material must be installed by a Qualified Installer who has been certified in the use of the HOME-FLEX® or VPC Alpha-FLEX™ gas piping systems. Installers must meet applicable qualifications set forth by the state and/or local administrative authorities which enforce the plumbing, mechanical, electrical and/or building codes at the locale where the gas piping is to be installed.
Fitting Assembly Table 4.2 Recommended Horizontal and Vertical Support Spacing for HOME-FLEX® Tubing Tubing Size Horizontal Support Spacing ½" (13 mm) 6 ft. ¾" (19 mm) 1" (25 mm) 8 ft. (USA) 6 ft. (CAN) Vertical Support Spacing 10 ft. 4.2 Fitting Assembly HOME-FLEX® fittings achieve seal by compressing the tubing into the gasket (Figure 4.2). It is critical that the cut end of the tubing is clean of any burrs or jagged edges, and that there is no debris on the tubing or gasket.
Installation Practices Step 2 Remove tubing jacket to prepare for fitting assembly Using a utility knife, strip the yellow pipe jacket back 2 valleys from the end of the tubing. DO NOT USE A TUBE CUTTER FOR THIS TASK AS IT COULD DAMAGE THE TUBING. Step 3 Place flange nut over HOME-FLEX® tubing Slide the HOME-FLEX® flange nut over the tubing with the threaded end pointing toward the end of the tubing. Do not push the nut beyond the catch on the jacket. The flange should cover the yellow tubing jacket.
Fitting Assembly Step 6 Attach flange nut to the installed HOME-FLEX® fitting Place the HOME-FLEX® flange nut onto the installed fitting. Hand tighten the fitting assembly from the nut-end, then tighten to the recommended torque value of 62 lb.ft (generally, tighten with force until the nut will no longer turn) using a second wrench to hold the fitting in place. DO NOT use sealant on the parallel thread of the socket.
Installation Practices Step 3 Place flange nut over HOME-FLEX® tubing Slide the termination flange over the tubing with the threaded end pointing toward the end of the tubing. DO NOT SECURE THE FLANGE. Step 4 Place retainer ring on HOME-FLEX® tubing Place the retainer ring in the first valley of the tubing. Being careful to not dent the tubing, clamp the retainer ring in place by applying gentle pressure 360° around the ring. It should fit tightly and not easily spin around the tubing.
a) Routing Proper fitting assembly. Make sure the gasket is installed in the base of the parallel thread of the fitting. If it was not, install the gasket, repeat assembly steps, and test for leaks again. Gaskets cannot be reused: if it was installed, replace it with a new gasket and continue to step 2b. b) Check for any obstructing material (dirt, shavings, jacket, etc.) in assembly. Remove material and reassemble, checking for leaks again. c) Integrity of assembly pieces.
Installation Practices the nearest edge of the wood structure (Figure 4.3). If this criterion can’t be met, the tubing must be protected by a striker plate of suitable size D/3 2" Max Min installed in accordance with Section 4.4 (p. 26). Preferred location The diameter of the hole should be no more than 1/3 the depth of the wood structure.
Routing vides test requirements which certify fittings for concealed installations and connections to appliances where concealing the fittings is the only practical alternative These guidelines address some of the known situations which may require the use of a concealed fitting. While accessibility of fittings is always preferred, there are some situations where concealing the fittings is the only practical option.
Installation Practices should be wrapped with self-bonding silicone tape, beginning on the jacket and ending on the nut of the HOME-FLEX® fitting. If HOME-FLEX® tubing is installed in an exposed condition alongside a structure between the ground and a height of 6 feet, the tubing should be installed in a location such that it won’t be subjected to mechanical damage, or be protected inside a conduit. HOME-FLEX® should never be buried directly underground.
Meter connections acceptable by CSA International for puncture protection. Steel pipe must have an inner diameter at least ½" larger than the outer diameter of the HOME-FLEX® tubing (Table 4.4). Protection must extend 5 inches beyond the peneTypical Wall Stud Typical Wall Stud tration of the structural members. A 12 inch pipe (Wood or Metal) (Wood or Metal) 1 length is acceptable for penetration of a single stud.
Installation Practices Connection by Special Termination Fitting Do not use HOME-FLEX® CSST as a direct connection if the meter must be supported by the piping system. If the meter is supported by the building structure, common practice is to route the CSST system to a termination flange mounted to the exterior of the building, and to connect the meter to the termination flange with rigid pipe.
Appliance connections Connections made between HOME-FLEX® and moveable appliances must be made with a HOME-FLEX® Flexible Appliance Connector, or similar approved device. Direct connections between HOME-FLEX® CSST and moveable appliances are not allowed. Direct Connection In most localities, fixed appliances may be directly connected to HOME-FLEX® flexible gas piping systems.
Installation Practices Any HOME-FLEX® tubing run vertically up the side of a building must be protected in accordance with "Outdoor Installation Issues" in Section 4.3. Outdoor Appliances: Barbecue Grills, Gaslights, and Heaters As with movable indoor appliances, movable barbecue grills, heaters, and other appliances should not be directly attached to HOME-FLEX® CSST.
Manifold Stations key valve or another location outside the fireplace. The final attachment to the lighter should be made using black steel pipe. Should HOME-FLEX® need to be installed through masonry materials in the fireplace construction, the yellow jacket should remain intact and the HOME-FLEX® tubing should be routed through a nonmetallic sleeve appropriate for the application. Sleeves are not required for routing through ceramic liner in heat generating fireplaces.
Installation Practices 4.8 Pressure Regulators Installation Requirements A HOME-FLEX® gas piping system used with inlet gas pressures in excess of ½ PSI, but servicing appliances rated for a maximum of ½ PSI, must contain a pounds-to-inches regulator to limit the downstream pressure to no more than ½ PSI. Gas pressure regulators must comply with a nationally recognized standard for pressure regulators such as ANSI Z21.80/CSA 6.22.
Underground Installations provides a cap for outdoor installations, this can be used and the regulator can be mounted right side up. Gas line regulators do not vent gas under normal operating conditions. A regulator that is venting gas should be replaced immediately. Performance Testing A performance test of the regulator should be conducted to confirm that adequate pressure reaches all appliances.
Installation Practices Ends of conduit do not have to be sealed Ends of conduit do not have to be sealed 11⁄2" minimum concrete cover 4" Min PVC or PE Conduit* No minimum burial depth beneath slab except as specified by local code Recommended minimum bend radius: 6" *ID of conduit should be at least 1/2" greater than OD of CSST Figure 4.
• Electrical Bonding Direct and permanent connection of a bonding jumper to the electrical service grounding system by connecting to the: electrical service equipment enclosure, the grounding electrode conductor (if of sufficient size), the grounded conductor at the electrical service, or to one or more grounding electrodes. The piping system shall not be used as a grounding electrode for an electrical system.
Chapter 5: Inspection, Repair, and Replacement of CSST 5.1 Minimum Inspection Requirements Checklist All installations shall be inspected by the authority having jurisdiction in accordance with state and local mechanical, electric, and/or plumbing codes, or in the absence of such codes, the National Fuel Gas Code (NFPA 54/ANSI Z 223.1), the International Fuel Gas Code (IFGC), the National Electric Code (NFPA 70), and/or the Uniform Plumbing Code (UPC), as applicable.
Repair of Damaged Tubing 5.2 Repair of Damaged Tubing If tubing is damaged before, during, or after installation, refer to these guidelines to determine the proper course of repair. Less than 1/2 D When Pipe Needs to be Replaced If the tubing is only slightly dented due to impact, it may not need to be replaced. A slight dent is defined as a dent less than 1/3 the diameter of the pipe and does not require replacement. (Figure 5.1) D Figure 5.
Chapter 6: Pressure Test Procedures The final installation must be inspected and tested for leaks in accordance with local and/ or state codes. In the absence of local guidelines, test the system at 1½ times the maximum working pressure, but not less than 3 PSI, using the procedures specified in Chapter 8 "Inspection, Testing and Purging" of the National Fuel Gas Code (NFPA 54/ANSI Z223). When local codes are more stringent, local codes must be followed.
Appliance Connection Check Procedure 6.3 Appliance Connection Check Procedure After the final pressure test, inspection, and final construction are complete, appliances may be connected to the HOME-FLEX® gas piping system. This final connection can be accomplished by a HOME-FLEX® Appliance Connector (or similar device), direct connection with CSST tubing, or with rigid black pipe, depending on the appliance (see Section 4.6 for installation details and guidelines).
Chapter 7: Sizing/Capacity Tables Natural Gas Sizing Tables Table 7.1 Low Pressure (6 - 7 in w.c. with 0.5 in drop) . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Table 7.2 Low Pressure (6 - 7 in w.c. with 1 in drop) . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Table 7.3 Regulator Outlet (8 - 10 in w.c. with 3 in drop) . . . . . . . . . . . . . . . . . . . . . . . 42 Table 7.4 Medium Pressure (12 - 14 in w.c. with 6 in drop) . . . . . . . . . . . . . . . . . . . . . . 42 Table 7.
EHD 18 25 31 EHD 18 25 31 Tube Size ½" ¾" 1" Tube Size ½" ¾" 1" Table 7.1 Low Pressure (6 - 7 in w.c. with 0.
42 69 60 64 70 62 75 80 90 100 125 150 200 300 400 500 60 57 54 49 45 39 81 28 72 25 50 96 60 89 70 86 75 80 90 100 125 150 200 300 400 500 84 79 75 68 62 54 45 39 35 31 2536 1720 1371 1167 1030 930 791 698 631 579 557 537 503 474 418 378 321 256 218 192 40 1" 30 25 1058 764 631 552 497 456 398 359 329 306 296 287 272 259 233 214 187 154 135 121 25 ¾" 20 308 222 184 161 145 133 116 104 15 18 10 ½" 5 EHD Tube Size Tubing Length (ft) Maximum Capac
Table 7.5 Elevated Pressure (2 PSI with 1 PSI drop) 70 75 80 90 100 125 150 200 300 400 500 Table 7.6 Elevated Pressure (5 PSI with 3.
44 150 200 300 400 500 42 41 39 37 82 30 71 26 58 22 85 50 19 75 45 17 10 15 20 25 30 40 50 60 322 232 192 168 151 139 121 109 100 5 93 70 90 75 Tubing Length (ft) 87 80 83 90 79 100 71 125 65 150 57 200 47 300 41 400 37 500 Maximum Capacity of HOME-FLEX® CSST in Cubic Feet per Hour (CFH) of House Propane Gas (Approximate 2520 BTU per cubic foot) Minimum Gas Pressure: 13 - 14 in w.c. Pressure Drop: 2.5 in w.c. (Based on a 1.
Table 7.
46 43 95 175 360 680 1400 2100 3950 6300 11000 23000 3/8" ½" ¾" 1" 1¼" 1½" 2" 2½" 3" 4" 10 ¼" Tube Size Table 7.11 Gas with a Pressure of ½ PSI or less and a pressure drop of 0.5 in w.c.
Chapter 8: Technical Information Sheet 8.1 Tubing Construction HOME-FLEX® Tubing: Type 304 Stainless Steel HOME-FLEX® Tubing Coating: Polyethylene Jacket 8.2 Fitting Construction HOME-FLEX® Fittings: C360 Brass HOME-FLEX® Retainer Ring: C360 Brass HOME-FLEX® O-ring: Silicone HOME-FLEX® High Temperature Gasket: Non-asbestos material 8.
Chapter 9: Definitions A.G.A. American Gas Association ANSI Z223.1 1988 The 1988 edition of the National Fuel Gas Code published by American National Standard Institute. Also known as NFPA 54 (National Fire Protection Association). Appliance (Equipment) Any device which utilizes natural gas or propane as a fuel or raw material to produce light, heat, power, refrigeration or air conditioning. Approved Acceptable to the authorities having jurisdiction.
Inches (“) Water Column (w.c.) Method of stating pressure measured in inches of water column by a manometer or pressure gauge. Commonly used in the gas industry when the pressure is less than one (1) PSI. ¼ PSI = 7 in. w.c. ½ PSI = 14 in. w.c. 1 PSI = 28 in. w.c. 2 PSI = 56 in. w.c. 5 PSI = 139 in. w.c. Joint A connection between two lengths of tubing or a length of tubing and fitting.
Regulator, Gas Appliance Pressure A device for controlling and maintaining a uniform pressure to the manifold of gas burning equipment. This valve is typically part of the appliance. It reduces the pressure from 5.5" w.c. to the manifold pressure in the appliance. Regulator, Line Gas Pressure (PSI to inches w.c.
Please PRINT Your Name Here I, ___________________________, have read the HOME-FLEX® System Design and DD YY Installation Manual and understand the installation requirements of the HOME-FLEX® CSST system. I am a Qualified Installer of gas plumbing per the governing local authority at the location where HOME-FLEX® is to be installed, and am aware of all local plumbing and/or building codes applicable to this location.
HOME-FLEX® certification can be completed online at: homeflex.
