I am looking to replace old metal underground fittings and valves supplying water to my house. The main supply line to the house after the water meter is 1" metal, which branches off with four 1" x 1" x 3/4" T's. I attempted to find a manifold to replace all of the fittings but no luck, so I decided to get PVC fittings and valves. But I was told by a plumbng supply house that I should use CPVC for domestic "potable" water and not PVC.

This application is only for the incoming cold water supply which banches off outside the house to four zones inside the house. The house is in Mantee county Florida, if that makes any difference.

Here's the questions...

Is PVC viable for potable cold water or do I need to use CPVC? Are there chemicals in PVC that make it advisable not to use it for drinking water? How about using PVC for showers and bath sinks? Should special glue be used for CPVC, or is regular PVC glue fine?

speedball1

Greetings from Whitfield Estates just North of the Airport in Manatee County.

This is why plumbing salesmen aren't out in the field doing plumbing.
We run all our water service lines from the meter to the house in PVC. (Poly Vinyl Chloride). We use CPVC,( Chlorinated Poly Vinyl Chloride) for the internal piping inside the house. PVC is acceptable for outside underground piping and PVC. PVc cement and primer may be used on the outside PVC but Use Oaty All Purpose Cement and CPVC Primer for the internal house piping.
Good luck, tom

LaMargarite

Thank you very much for the quick response. If you don't mind, my inquisitive side would like to know why CPVC is used inside the house even when it would be for a cold water line that originates from PVC outside the house.

speedball1

" If you don't mind, my inquisitive side would like to know why CPVC is used inside the house even when it would be for a cold water line that originates from PVC outside the house."

It all depends on heat. CVPC will handle higher temperatures then PVC pipe. PVC upper temperature limit is 140 F while CPVC is 220 F although the two are very similar in terms of chemical resistence.
Since you don't encounter high temperatures outside the house PVC's acceptable for potable water. Next question!! Regards, Tom

senthil4you

How will you compare gi pipes with cpvc?

LaMargarite

I need to use a CPVC male adapter to attach a tub spout to a 1/2" CPVC water supply. But, the male adapter sold at Lowes and Home depot indicates "For Cold Water Only" on the box.

Can it actually be used for Hot & Cold water or is there an issue with using male adapters for hot water? Or, are there different ttpye of male adapters that are for hot & cold water?

speedball1

There's no comparison between galvanized and plastic pipe. Galvanized will allow mineral buildup to the point where volume and pressure's affected plastic will not. The last time I can remember piping a house in galvanized was up in Wisconsin over 50 years ago before we moved to Florida. Regards, Tom

You didn't read my last post very well did you? It's quite likely that you won't be using water over 120F so a PVC adapter should do fine but if you're concerned purchase a CPVC male adapter.
Regards, Tom PS. what section of Manatee county do you live in?

AllTrades

Sorry to be answering this question a whole year too late. But it will probably benefit someone else.

The answer to the question about CPVC fittings is here: http://www.ppfahome.org/images/CPVC_...tion_FINAL.pps

The answer is that there are two kinds of fitting: Adapters are designed to change configuration (e.g. slip to thread). Transition Fittings are designed to change material (e.g. CPVC to Copper).

Do not use Adapters to change material with hot water. For example, you could glue a slip-to-MPT Adapter to your CPVC, and then thread that into a FPT copper adapter. This would work for cold water, and would leak hot water. The reason is that copper and plastic have different rates of thermal expansion, and you are counting on the threads to for the water tight seal.

For hot water, you must use a Transition Fitting. This has an internal O-ring (see cutaway diagram in the link above) which provides a seal. You could also use a CPVC female adapter with a built-in elastomeric gasket, or a CPVC-to-Copper Union. The reason you can use these with hot water is that the seal is not provided by the threads.

speedball1

You're a little late but good information about the CPVC to copper Transition Fittings,(see image). thanks, Tom