Frequently Asked Questions
Q. "Will these CPVC fittings glue onto regular PVC piping?"
A. The CPVC fittings we offer on this page will not glue on PVC schedule 40 pipe. The CPVC fittings offered on this page are Copper Tube Sized (CTS) and normal Schedule 40 PVC pipes are sized according to IPS (iron pipe size) standards which are slightly larger in diameter. CTS sized piping has the same outside diameter as copper piping. 1/2" CPVC fittings fit CPVC piping that is 5/8" O.D.. 1/2" Schedule 40 PVC fittings fit PVC piping that is 27/32" O.D.
Q. "Can I use CPVC pipe/fittings for compressed air or gases?"
A. Although some people use CPVC piping for compressed air or gases, we are not aware of any fittings manufacturer that recommends it. We believe it is dangerous and absolutely do not recommend it. Air is much more compressible than are liquids and could therefore cause a violent explosion.
Q. "Can I glue CPVC if it is wet?"
A. All solvent cements have the ability to absorb some water and still perform well enough to affect an adequate joint. However, research shows that the presence of just 10% water in solvent cement can slow penetration and swelling by up to 65%. This joint with water inside will always be an inferior joint and subject to problems.
Q. "How long should I wait after I've used solvent on a CPVC fitting before pressurizing the system?"
A. In most situations, to be 100% sure of no leaks, we recommend waiting 24 hours before pressurizing a system.
Q. "I get confused about CPVC sizes. You say that yours is 'copper size' but then you say that it is 'schedule 40' which I always thought meant the same size as steel pipe like galvanized. Please help to understand?"
A. Schedule 40 is the class rating of the pipe in regards to operating pressure, operating temperature and wall thickness of the pipe. There are two "standard" sizes of CPVC; IPS (Iron Pipe Size) and CTS (Copper Tube Size), which makes it a bit confusing. CTS matches the outside diameter of "nominal" copper pipe and tube, which is the type we offer. For example, the copper tube size 1/2" CPVC that we sell has an outside diameter of 5/8" and the 3/4" CPVC outside diameter is 7/8". CPVC made to IPS (iron pipe size) standards match the outside diameter of PVC pipe and comes in Schedule 80. We do not offer fittings for IPS sized Schedule 80 CPVC. Please Note: CTS (Copper Tube Size) CPVC, where it is allowed by code, is acceptable for residential plumbing.
Q. "I've had a few female adapters break. What am I doing wrong?"
A. Many codes (such as UPC 1994 sec606.2.2) prohibit female PVC screwed fittings for water piping. The reason is, pressure is exerted outwardly, and eventually a female adapter can crack. We always recommend using male adapters (with metal female fittings rather than the other way around). Never use regular female adapters with pressures over one pound.
Q. "Do you have any information regarding a product called FlowGuard™?"
A. Flowguard™ is a trademark of B.F. Goodrich's CPVC products. It normally has a yellow stripe on the pipe. There are other brands of CPVC.
Q. "What about 'fast' or 'hot' CPVC glues? Don't they glue faster?"
A. Normally the 'fast' or 'hot' CPVC glues have a faster set time. Cure time for most is still about the same. "Set" time is the initial period of swelling required to give the joint enough mechanical strength to be gently handled. "Cure" time is the total time period of required swelling for the joint to acquire enough strength that it can perform its job transporting materials through it at whatever pressure and temperature required without coming apart or leaking.
Q. "Can I use CPVC glue on other plastics?"
A. We only recommend using glues manufactured for a specific plastic i.e. CPVC glue only on CPVC pipe.
Note: There are many plastics that cannot be glued at all; polyethylene, polypropylene, nylon, polybutylene, and other polyolefins.
Q. "What is LO-V.O.C.?"
A. LO-V.O.C. cements produce significantly less amounts of "V.O.C.'s". V.O.C. stands for "volatile organic compounds", which are unhealthy when breathed or induced. V.O.C.'s also diminish air quality. Please read and follow all directions carefully when applying these cements.
Q. "Do I really need to use primer as I have a 'one step' solvent?"
A. Primer is a mixture of solvents used to penetrate the pipe and fittings and start the swelling process ahead of the application of the solvent cement. We highly recommend that you use primer anyway.
Q. "Do you offer CPVC primer?"
A. We have not found a brand of primer that we are confident will not leak in transit. It is highly flammable and, in our opinion, too dangerous to ship.
Q. "Do you recommend using PTFE thread sealing tape on CPVC threads?"
A. Lasco Manufacturing says (when speaking about a similar plastic, PVC): "It is wrong to add excess bulk to a threaded joint by wrapping male threads in Teflon® tape. It is wrong to make over-tightening easier by using Teflon® tape..." We have seen much similar PTFE thread sealing tape used satisfactorily but cannot (due to liability potential) recommend that you use PTFE thread sealing tape (pipe dope designed for CPVC, such as we offer here, is acceptable).
Q. "Do I have to do anything special when I'm gluing a CPVC valve?"
A. Before installation, make sure the valve is in the "open" position and all cemented surfaces are clean and dry. Install the valve following the established solvent procedure. A suitable support should be placed under the valve body to hold the weight of the valve. Be sure to adhere to proper curing times, and wipe off any excess cement that might have accumulated at the joint bead.
Q. "Will CPVC pipe and fittings crack when it is frozen?"
A. Just like copper, it will. If your pipe/fittings will be subject to freezing then you might consider looking into PEX pipe.
Q. "Can I get a price break if I buy in volume?"
A. Yes. If you buy in quantities stated on the page of the same fitting, you will receive a discount from the prices listed. Discounted prices will appear in your shopping cart.
Q. "Do you offer British Standard Threads (BST) or metric fittings?"
A. Sorry, we only sell U.S. threaded fittings.
Q. "What are the new lead-free plumbing laws?"
A. The new lead-free laws require plumbing products that come into contact with drinking water to be essentially lead-free (0.25% weighted average). In order for companies to ship these products to locations in states with these new lead free laws, they must be ANSI certified lead-free.
Q. "I'm hearing a lot about lead-free these days. What does that have to do with plumbing products and how does the new lead-free legislation affect me?"
A. Basically, the laws implemented Jan. 1st, 2014 require plumbing products that come in contact with drinking water to be essentially lead free (less than 0.25% weighted average). For further information about how the law determines what is lead free, rules regarding which plumbing products must be lead free, and who these laws will affect, please visit our LEAD FREE Plumbing Information page.