Galvanized to PVC Question

[Primemover]

In my situation there is not enough room between the galvanized fittings to cut and have a stub big enough to use a no-hub adapter. I am working with a 1-1/2" waste line. I am wondering if I can connect one side of a No-hub adapter over the female portion of a galvanized fittings (maybe use a 2" to 1-1/2" no hub?) And the other to the PVC? Or am I not allow to put it of a fitting and it NEEDS to be on a "regular" section of pipe? (the "regular" section is under the floor on the second story and I don't want to pull the floor up).

Or should I try using a PVC 1-1/2" male threaded adapter to connect the PVC to the female end of the galvanized fittings (could someone recommend the correct adapter?)

Thank you for your help in advance!

 

[Reach4]

Instead of "no-hub" I suggest you use the term shielded coupling. The term no-hub is usually used for some cheaper connectors for cast iron. Maybe those can be used for regular drain stuff. I don't know. I am not a plumber.

If the threads are good enough consider http://www.proflo.com/product/proflo-PF2020-n-a-1191103 You can mix metal and plastic. There are other brands and finishes.

Consider cleaning the thread with a brass brush. Use PTFE tape and pipe dope both.

 

[Sponsor]

 

[Sylvan]

When dealing with a plumbing supply and you use the term NO HUB coupling the majority will automatically use the shielded coupling

Big box stores and the unknowing may sell a Fernco coupling which is not even to be considered IMHO

The problem using this connection to a galvanized nipple is it will cause galvanic corrosion (electrolytic action) Not a great idea to mix dissimilar metals such as ferrous sand non ferrous metals

 

[Reach4]

You could cement a 1-1/2 in. PVC Sch. 40 MPT x S Male Adapter into a 1-1/2 in. PVC DWV Hub x SJ Trap Adapter, and have an all-PVC solution. Use PTFE tape and plastic-safe pipe dope (both) on the threads in that case.

 

[Jadnashua]

By far your better path would be to trash all of the galvanized piping. Especially on hot lines, it rusts from the inside out. The threaded ends cut through the galvanized coating and provide a ready point for rust to occur. Heat tends to make it happen faster.

 

[Primemover]

Thank you all for the advice!