Can a pvc pipe go into a cast iron 90degree elbow or do I have to replace the elbow with pvc elbow? (all this is underground in my kitchen)

Hey Blade...

If you use a proper transition clamp or fittings then yes... PVC can attach to cast iron pipe.

Can use shielded clamp (proflex or mission style SS banded.. see pic.) or can use threaded male or female adapters with teflon tape on threads (see pics.)

Let me know if this is what you needed...

MARK

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