Ask Me Help Desk - PVC to old copper drain

I would like to know the best way to transition a 2" ABS pipe to a 1.5" copper drain pipe. The 2" drain will be attached to a shower drain.

An image of the current drain system is attached.

Originally, I was planning to use the copper to ABS adapter sold at HD. Would there be any issue transitioning from the 2" to the 1.5" horizontally?

Thank you in advance,
Joe

Quote:

Originally Posted by NoviceCanada

I would like to know the best way to transition a 2" ABS pipe to a 1.5" copper drain pipe. The 2" drain will be attached to a shower drain.

An image of the current drain system is attached.

Originally, I was planning to use the copper to ABS adapter sold at HD. Would there be any issue transitioning from the 2" to the 1.5" horizontally?

Thank you in advance,
Joe

Hi Joe,
Is the upper 2" ABS pictured that you wish to connect? Not too much detail to go on as I can't make out the present connection. But I would make the terminal tie in a ABS or PVC 2" female slip to 1/1/2" compression adapter. Good luck, Tom

Quote:

Originally Posted by speedball1

Hi Joe,
Is the upper 2" ABS pictured that you wish to connect? Not too much detail to go on as I can't make out the present connection. But I would make the terminal tie in a ABS or PVC 2" female slip to 1/1/2" compression adapter. Good luck, Tom

Hi Tom,

Thanks for the quick reply. No, the 2" ABS you see is a vent pipe which runs from the basement and then across the second floor joists (as seen in pic) to a cast stack on an opposite wall. There is no water or waste draining into this 2" ABS. To the best of my knowledge, this is venting for the 1st floor bathroom.

I have attached another photo (top view). From the photo, near the middle, you can see the wye collar (attached to the 4" cast stack) which has two 1.5" copper drains attached to the wye. I would like to take the copper pipe towards the bottom left and cut it before or after the elbow and attach the adapter. A couple of questions.

1) Should I attach the ABS or PVC 2" female slip to 1/1/2" compression adapter horizontally or on a 45deg angle (depending where I cut the copper pipe)?
2) Are there any concerns attaching the ABS or PVC 2" female slip to 1/1/2" compression horizontally? Do you recommend any other measures to ensure a tight (hopefully) leak proof compression/seal?

The copper pipe to the right will be used for a sink.

Thank you again.
Joe

Quote:

Originally Posted by NoviceCanada

Hi Tom,

Thanks for the quick reply. No, the 2" ABS you see is a vent pipe which runs from the basement and then across the second floor joists (as seen in pic) to a cast stack on an opposite wall. There is no water or waste draining into this 2" ABS. To the best of my knowledge, this is venting for the 1st floor bathroom.

I have attached another photo (top view). From the photo, near the middle, you can see the wye collar (attached to the 4" cast stack) which has two 1.5" copper drains attached to the wye. I would like to take the copper pipe towards the bottom left and and cut it before or after the elbow and attach the adapter. A couple of questions.

1) Should I attach the ABS or PVC 2" female slip to 1/1/2" compression adapter horizontally or on a 45deg angle (depending where I cut the copper pipe)?
2) Are there any concerns attaching the ABS or PVC 2" female slip to 1/1/2" compression horizontally? Do you recommend any other measures to ensure a tight (hopefully) leak proof compression/seal?

The copper pipe to the right will be used for a sink.

Thank you again.
Joe

Hi Joe,

1) Should I attach the ABS or PVC 2" female slip to 1/1/2" compression adapter horizontally or on a 45deg angle (depending where I cut the copper pipe?
Cut the pipe after the elbo so you will have enough stock for the compression fitting. Makes no difference to the fitting whether it's horizontal or on a 45 degree angle.

2) Are there any concerns attaching the ABS or PVC 2" female slip to 1/1/2" compression horizontally? Do you recommend any other measures to ensure a tight (hopefully) leak proof compression/seal?

Answered above about the horizontal installation. I can see no problem using a compression fitting. We use them all the time hooking up sinks and other drainage. Good luck Tom