Is this 4 band no hub mission "heavy coupling" suitable for transitioning 4" PVC Sch 40 to Cast Iron? "4MED" read on bell up stream. Do I need to use a pvc soil adapter?

I am going to cut a few in. before the bell.

Thanks







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Yes, that's what you need to use. You won't need anything else.

Ok because I just test fitted it and have to stretch the rubber sleeve a little by itself without clamps to fit on the PVC.

Technically, it it NOT the proper coupling, although it will work, but our inspectors would reject it. The proper one would be a transition coupling specifically for plastic on one side and cast iron on the other.

I ran into the same issue about two years back and asked the same questions.

If I remember correctly at the time I was looking at two options.

(1) Fernco at the time makes a specific transition coupling from CI to PVC. The sleeve has slightly different thickness on each side, very subtle because it is very close.

(2) Use a standard no hub coupling, but glue a PVC no hub adapter to the PVC pipe, presumably it adds rigidity to the joint some.

Or just use a no hub coupling because it is close enough.

I end up using a PVC no hub adapter because the local plumbing store has the adapter, but not the special transition coupling.

quote; glue a PVC no hub adapter to the PVC pipe, presumably it adds rigidity to the joint some.

Not really, it just makes the PVC the same size as the cast iron so the No-Hub coupling works "properly".

hj, the problem is, when I held the no hub adapter next to the PVC pipe, they look to have the same OD. I am not sure the no hub adapter is the same OD as the CI, or may be it is but not appreciable visually.

I heard many people said it's a better joint, so I use it, but I haven't found a good valid reason.

I heard as many people said it's not necessary because the difference in CI and PVC OD is not enough to make a difference. Yet Fernco used to make one with the sleeve thickness being slightly different. I don't think they make that version anymore.

Now one thing I found, was the no hub adapter has a real smooth and round "end" to it. So when you push the sleeve onto it, there is zero chance of that being cut, nick or ripped, where a freshly cut PVC pipe may have a more sharp edge.

I would also like to ask anyone's opinion on adding a cleanout before the band.

Thinking of using a smaller "test T" instead of a "rodding T" to keep it from blocking the breaker box.

quote; I haven't found a good valid reason.

Actually, there may not be a "valid reason" other than that the inspectors "want it". They LIKE to see a coupling labeled PVC/ABS on one end and cast iron on the other even if both sides are the same size.



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You can do whatever you want to.

Should a cleanout be installed with wye slanted towards flow, or can a test tee cleanout be placed on its back horizontally and rolled no more than 45* from center? Would that negatively affect flow since the joint is perpendicular?

Also wondering if ya'll think this elbow needs to be supported permanently once connected to PVC (my guess is YES).



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Mission Web site states 80 in/lb on this coupling, should I go less with the PVC being used? Other band seal transition couplings are usually 60 in/lb.

Thanks

Yes, support the 90.
Use a test tee.
80 inch pounds won't hurt the PVC.

Unless you are using an adjustable No-Hub wrench, or a special one for those couplings, all you are going to get is 60. You install cleanouts as necessary to provide access to them, without impeding the drainage flow.

Ok so would a test Tee before the elbow not impede drainage? I will have to rotate it 45* off top center.

IF it is installed correctly, then it is just a short piece of pipe with a plug in it. Obviously, you do NOT rotate the plug so it is in the lower half of the line.



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How taut should a hanger strap be in supporting that 90?

HJ, I would like to replace the 90 as well but am aware of the DIY difficulty in removing a lead joint in order to insert a donut, if that is even the existing connection buried in the wall.

There is a joint "buried" in the wall, but it is NOT at the surface and YOU do not have the equipment or experience to replace it.

I will not argue you on that point. I don't even have a cold chisel. I can just see the hub of the pipe in the wall as I scrape away some of the dirt around it.

hj, what is your advice on supporting the elbow enough so that it does not disturb that in wall connection?

NOTHING is going to "disturb" that connection in the wall. LEAVE IT ALONE.