The water supply coming from our well is 1" PVC pipe. The main water lines in our house are 3/4" CPVC. What is the best way to connect the two?

Can the two types of PVC be solvent welded together? If so, do I use PVC or CPVC glue?

My first thought is to use a 1" PVC coupling with a 3/4" PVC FIP threaded bushing. Then to use a 3/4" male adapter on the CPVC side. But, I know that plastic female fittings are not really recommended.

I suppose I could use a 3/4" brass coupling with a PVC male adapter on one side, and a CPVC male adapter on the other?

Anthony

Can't glue dissimilar plastics together.

The brass coupling idea with male adaptors for each type of piping is the right thinking.

I would use a 1"brass ball valve and a male adapter on the pvc, and a 1 X 3/4" brass bushing and a 3/4" cpvc male adapter on the other side.

> I would use a 1" brass ball valve and a
> male adapter on the pvc, and a 1 X 3/4"
> brass bushing and a 3/4" cpvc male adapter
> on the other side.

I had considered something similar, but I already have a valve 1 foot away above the floor (easier access). Placing the valve in the crawlspace would mean crawling about 25 feet just to turn off the water. Not something I would want to do if a pipe suddently breaks. I can always shut off the water at the well if I need to work on stuff in-between.

Anthony

> Can't glue dissimilar plastics together.

That was my understanding, but I saw a fitting at the local home center that was specifically called a "CPVC to PVC Adapter". It was a single piece of plastic, and appeared to be CPVC. I didn't buy it because I couldn't figure out how you were supposed to glue it up.

> The brass coupling idea with male adaptors
> for each type of piping is the right
> thinking.

That's probably what I'll go with.

Thanks again!!!

Anthony

They make all purpose cement; it is used for ABS, PVC, CPVC and maybe another I can't recall right now. I've used AP cleaner and cement and the transition couplers/adapters and have not had any problems. I also use PVC. Nylon and CPVC threaded fittings (females) and I've never had problems with them either. But I'm the kinda guy that learns how to use the stuff as it is designed to be used, which mostly means not tightening things to tight and causing them to break. I have worked on well water systems for 15 years and they make up 99.9% of my business in both water treatment and well water systems. If you do it right, proper All Purpose cleaner/primer and cement (or specific product cleaner and cement for each type material) you won't have a problem with female fittings or glued transition adapters/couplers. Teflon dope for plastics or 3-4 wraps of tape and don't over tighten and you'll be fine.

Gary
Quality Water Associates

Gary, I highly respect your experience and vast knowledge and have learned a lot from you. I am not trying to criticize you but I do want to clarify something.

I think you know that PVC and CPVC are close as far as plastics and so should be ok to solvent weld together

BUT

ABS is totally a different chemical composition of plastics compared to PVC and CPVC.

Most plumbing codes state explicitely that they are not allow them to be glued (solvent welded) together.

Not even with the best AP (all purpose) glue.

We don't "glue" plastics, we "solvent weld" them and using dissimilar plastics is not allowed in plumbing codes for good reason, as they can't chemically do that.


As far as using female plastic adapters, most plumbing codes do not allow them.

Thanks for the kind words. No offense taken, I'm here to learn too. I'm not a plumber so I suppose I should be more careful about what I say and the terminology, such as solvent weld and glue etc.. I also don't know codes. I also don't like many codes that are politically driven and/or lack common sense. Furthermore, a homeowner should be allowed?, let's say can use, whatever s/he desires if s/he can find it available in their area. They can worry about meeting code later in life if they sell the house etc.. I think solvent weld and gluing or cementing is chemically the same. Maybe I'm technically wrong?

From my perspective here in PA. Waht would you suggest in these situations? Here we have some wells with the first ever sch 40 plastic pipe which is/was ABS. It's been in the ground, basements to the tank and down the wells for 40 years. We have adapters that connect it to sch 40 PVC. We use All Purpose cleaner/primer and cement that says it can be used on ABS. Your thoughts?

I also use it for the distributor tube material in 99% of all the softeners I've seen over the years. I use AP cement to 'attach' the bottom basket to the tubing material. I'm not alone in doing this but many in the business use methelethelketone(sp) or some such, but I'm too lazy to get the gallon jug down off the shelf and keep the squeeze bottle filled. Plus it runs all over and I don't like it.

Gary
Quality Water Associates

"....I think solvent weld and gluing or cementing is chemically the same. Maybe I'm technically wrong?"

Yes, you are but words aren't what is important here.

What is important is for you to recognize that you can not really "solvent weld" (which is what you desire to do, making the materials and the fittings of equal strength) to TOTALLY different plastics together.

The word "plastic" is very vague and generic.

As you know, not all plastics are alike.

I think you recognize that you can't solvent weld PB or PEX at all.

That is because of their chemical composition.

ABS is acrylonitrile butadiene styrene (sorry if I misspelled it) and as you know, PVC is poly vinyl chloride.

Radically different compositions and not chemically possible to solvent weld.

Glueing sure but not chemically welding them together.

I agree that many of the reasons for some plumbing code rules is political but I am certain that the not allowing solvent welding PVC and AB together is not politivcally motivated.

Mechanical joining is the only legal jopining allowed in most codes.

If anyone who glues (can't solvent weld) PVC and ABS together and it blows apart, they should be held accountable.

Glueing PVC and ABS together on non pressure joints might be different and not that critical but note that in most plumbing codes, even low pressure drainage fittings aren't allowed to be glued together.

I know of no plumbing union or politician or special interest that gains because of this law.


Jim



Post Edited

Jim, I can understand plumbers being told and made to follow codes to protect their license. But as the 'plumber' working on my customer's no water call, I'll not be telling him he has to dig up and replace his ABS pipe back to the pitless adapter on the well casing because code says I can't install the fittings I have in the van for his pipe sizes to convert to PVC so I can replace his pump that's burned up.

Do know that PE can be heat welded? And I would suspect PEX could be also. I don't know that it is though but PE is. Anyway, the poster here and my customers that I do this for are on their own wells with max pressure, set by code, of 75 psi if they install the 'required' PR valve (sub pumps only). Otherwise it's the maximum pressure their well allows their pump to deliver.

Gary
Quality Water Associates