BlazeMaster CPVC fire sprinkler systems have been protecting people and property for nearly 40 years. Many of the systems constructed as far back as 1984, when BlazeMaster Fire Protection Systems was launched, are still in service. Because of CPVC’s long life expectancy, these older systems can perform just as well as newer ones.
While metallic systems corrode and need to be replaced as they age, older BlazeMaster CPVC is readily repaired by following well-established best practices. These “cut in” procedures are important because the chemical properties of CPVC change over time. It’s a normal process that does not compromise the pipe’s performance. In fact, the pressure-carrying capabilities of the pipe increase as it ages.
Impact resistance also changes, which has little effect on the installed system. That means that when cut-ins are needed, workers must take precautions to prevent damage to the existing system and ensure continued system strength and integrity. Here are seven steps to ensure success:
Know the age of the system before you start cutting. There is no hard-and-fast rule about when and if CPVC becomes brittle. But start by checking the placard in the riser room to find the installation date. That will give you a sense of whether you might need to use extra caution on the project.
Cut into the smallest diameter pipe section near the modification using a fine-tooth saw or approved tubing cutter. With aged pipe, it is critical to use the right CPVC pipe cutting tool. Do not use a conventional ratchet cutter – it will squeeze or flatten the pipe. Because aged pipe is more brittle, the ratchet cutter can cause cracks that may not be seen with the naked eye.
Ensure the pipe is dry before solvent welding. Any moisture will slow the curing process and could ruin the joint. Drain the lines prior to solvent welding using an industrial vacuum cleaner. The drain vacuum is installed at the riser and will suck water out of the drop. But don’t stop there – use a rag and/or a hair dryer to remove any traces of moisture.
Follow installation best practices as you measure and cut CPVC. Square cut the pipe to length. Debur, bevel and wipe the pipe before applying solvent cement and inserting with a quarter turn. Use a fresh can of solvent cement to ensure you get a perfect weld. Remember – solvent cement is not “glue.” Unlike glue, solvent cement bonds with the CPVC to create a continuous run of pipe. A brand new never opened can of solvent cement has the best welding power. For more details, download our Complete Guide to Solvent Cement and CPVC Fire Protection Systems.
Reference cure times for cut-ins – they’re different than new installation. Check our Cure Schedules for BlazeMaster CPVC. Get as much time as possible, even beyond the recommended cure time, to ensure the welds are ready for testing. Keep in mind that the cure times assume that the pipe and fittings are dry. Cure times increase – sometimes dramatically – if water is present.
Once fully cured, slowly fill with water. Bleed air from the furthest and highest sprinkler head.
Pressure test in an isolated area. Do not exceed 50 psi (345 kPa) over operating pressure, and do not use compressed gas.
As always, reference the manufacturer’s installation instructions for additional information.
By following these steps, you can ensure successful repairs and cut-ins that further extend the lifespan of a BlazeMaster CPVC fire sprinkler system – and keep your customers happy. For more in-depth information, we cover this topic in our live online training sessionsor our self-paced program.
As always, if you have questions about upcoming projects – repairs, cut-ins and anything else – technical support is just a click away.