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Plumber Manhattan Beach
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Leaking 2 pvc line under asphalt.jpg

Repaired 2 pvc line under asphalt.jpg

2 Feet deep under asphalt. Leak Location guy was 8 feet off. Don't blame him. It was a small split in the repair coupling instead of a full on broken joint.

Repaired with 2" copper scheduled 80 fittings and viega propress fittings.
 

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Are those Copper x MIP adapters or FIP adapters? Hard to tell.
I can't stand any threaded transition from metal to plastic. But if you HAVE to, the best is to use a Copper x FIP with a plastic x MIP threading into it, but this is only if there will be very little temperature change. If you are going to see wide swings in temperature change, then you must use the plastic FIP that is pre-stressed with a metal ring and screw a Copper/metal x MIP into it, or if they make a plastic by MIP where the MIP is some type of metal i.e. brass into a metal x FIP.

Also, many plastic manufacturers are extremely leary about you using pipe dope on any threaded adapter from metal. Supposedly from what I've heard it's teflon only.

Also, is that the same one step PVC glue that the swimming pool guys use?
 

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Plumber Manhattan Beach
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Discussion Starter #3
Are those Copper x MIP adapters or FIP adapters? Hard to tell.
I can't stand any threaded transition from metal to plastic. But if you HAVE to, the best is to use a Copper x FIP with a plastic x MIP threading into it, but this is only if there will be very little temperature change. If you are going to see wide swings in temperature change, then you must use the plastic FIP that is pre-stressed with a metal ring and screw a Copper/metal x MIP into it, or if they make a plastic by MIP where the MIP is some type of metal i.e. brass into a metal x FIP.

Also, many plastic manufacturers are extremely leary about you using pipe dope on any threaded adapter from metal. Supposedly from what I've heard it's teflon only.

Also, is that the same one step PVC glue that the swimming pool guys use?



Of course they are Brass Propress FIP'S with schedule 80 MIP's threaded intot hem. This is a 2" main, I cut out an old repair that failed and completed mine. The glue is called WET N DRY, and the primer is a purple primer.

I have been doing this along time, and I have seen the floods caused by people screwing metal into plastic. You always screw plastic into metal :thumbsup:
 

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Is that glue specified by the manufacturer of the PVC pipe? (not criticizing, just asking, nor do I intend to come accross as questioning you personally).

One of our sales reps for Emco up here is a member/consultant for all of these various boards that discuss materials that have various certifications. The guy has an extreme wealth of knowledge behind the various materials that are approved and the problems associated with them, as well as their quirks, in the Plumbing Industry. You could literally have an hour long conversation with him and not even see the time go by because he is so knowledgeable about various products out there and his experience on these various committees is that much in depth. One of the things he related to me recently and I've heard this before, is when using glues, and primers for PVC pipe especially, it is in our best interests to use glues produced by the manufacturer of the pipe or at least specified by them. He says the critieria of what makes a class of PVC pipe and class of glue has a fairly wide spectrum and so one manufacturers glue is not neccessarily the best for anothers pipe and vice versa.

There ARE plastic FIP fittings out there designed to have metal screwed into them. In fact they are better at handling temperature swings (i.e. heating mains) than a plastic into metal. In fact a plastic into metal WILL leak when used in lines with wide temperature swings but metal into the plastic that is prestressed with the ring will not. I believe there are however, some plastic manufacturers of PVC and CPVC (not IPEX though) that do have an MIP adapter that is reinforced with metal to allow it to handle temperature swings when screwed into metal FIP's.

Yeah I'm sure I'm going to hear x and x a story about someone who did this but I'm one who likes to do it by the book.
 

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Scott K

According to UPC only plastic male to plastic female threads are only allowed, nothing else. CPVC does have a reinforced brass insert in them but not PVC.
 

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Plumber Manhattan Beach
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Discussion Starter #6
There aren't any temp swings on this line.

Plastic always gets screwed into metal, atleast here in southern california we never have problems with it cracking. If this was another type of line carrying hot and cold material, then I will investigate further. This line only carries cold water.

The WET N DRY glue is the best for this application, seeing as we repair these lines atleast once a year in different areas, and we can never get he water to stop and how we have repaired multiple other areas witht he same glue, we have not had any issues to date. In my book, WET N DRY and purple primer is the best way to go with any PVC, I sand my fittings and pipe and prime and glue, this in my book is the best way, the only other way is to sweat or press the fittings in copper, get rid of PVC all toghether.
 

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In my area the new construction guys love to tie onto the meter nipples with PVC FIPs. I get lots of water service repair calls because of it. I install a threaded brass coupling on the nipple and use a PVC MIP. If I don't have a brass coupling I install sch80 FIPs in their place with 1/2 turn past hand tight with tape on the male threads and Teflon dope on the females.
 

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Ron,

I'm Canadian - Canada develops a new National Code every 5-8 years and then each Province adopts this new National Code for their Provincial Code with certain amendments, but the latest edition of the National Code was so good that there are very, very few amendments for each Province I'm told. You will find if you ever have the chance to read the Canadian National Code, that is as good or better than what you go by seeing as how Canada typically deals with some pretty harsh environmental conditions for the most part. Having said that I"m not sure if in our Plumbing Code, such a rule exists, but I do know that Inspectors will fail an inspection if you screw a metal into a plastic if the plastic FIP isn't designed for said purpose.

Ipex has a PLASTIC Female adapter that is prestressed with a metal ring around it. This fitting is designed so that you can screw metal MIP fittings into it. They make them for both Sch 80 PVC (Xirtec) and Sch 80 CPVC (Corzan) as well as for their Aquarise (CPVC) lines. These fittings are the only fittings that will tolerate swings in temperatures and not leak made by Ipex anyways, that I know about. I'm sure you've probably seen other manufacturers that have a brass FIP that is impregnated into the plastic adapter too. The Polypropolene adapters & saddles I fuse (Fusiotherm/Aquatherm) are of the type with a brass FIP impregnated into a plastic adapter.

If you screw a plastic MIP into a Metal FIP, the joint WILL leak if it is expanded and contracted due to temperature change of the water in the pipe. This is mainly in heating systems, but could possibly happen in a hot water line where CPVC was used.

Whether or not Wet N Dry is the right glue or not is not up to me. I was just merely relaying information more so than anything. In a lot of cases, you should be pretty safe following manufacturers instructions/specifications and that is what I tend to do.

Apparently North America in general is known for having fairly tight codes, but looser restrictions on products, where as in Europe that have very tight restrictions on products - they don't get sold, and a bit looser restrictions on codes.
 

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I always use a PVC sched 80 MIP into brass or copper FIP. Purple primer with the heavy duty PVC glue, haven't had a problem yet.
 

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I use "Muller" or "Ford" couplings only, No drying time, in 15years never a problem. EXPENSIVE but the only way to transition in the ground. Just repaired a 2" PVC #150 air line at BNSF Ballard in December.
 

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Dressler couplings do the same as well. Those Ford couplings look to be Spendy!! Who's your supplier on those?
 

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on anything above 1" I use a Ford brass pack joint coupling for two dissimilar metals
CTS x PVC. these work great and I have never had a problem with them
 
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