Kitchen drain line question
#1
Member
Thread Starter
Join Date: Jul 2008
Location: canada
Posts: 334
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Kitchen drain line question
I like to replace the 1 1/4'' drain pipe with 1 1/2'' ,the vent behind it is 1 1/2''
Is there a way to to do this without replacing the CI double Y?
Thank you
Is there a way to to do this without replacing the CI double Y?
Thank you

#2
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 38 Upvotes
on
30 Posts
Assuming that the piping on the right side of the picture is the drain you wish to replace, the answer is no. You need to replace the double wye. The rule is that you cannot run a larger drainage pipe into a smaller fitting.
#3
Member
Thread Starter
Join Date: Jul 2008
Location: canada
Posts: 334
Upvotes: 0
Received 0 Upvotes
on
0 Posts
I see I didn't phrase the question correctly
Is there a way to install a 1 1/2'' fitting without replacing the double Y ?
The drain is the pipe coming strait down, top of the DY
Is there a way to install a 1 1/2'' fitting without replacing the double Y ?
The drain is the pipe coming strait down, top of the DY
#4
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 38 Upvotes
on
30 Posts
Same answer, if the female threaded fitting in the cast is 1-1/4 you cannot use a 1-1/2 above it. AND if the outlet is still 1-1/2 you are completely out of luck.
Now I'm curious, the vent should be the center line, what is the line coming in from the side?
Now I'm curious, the vent should be the center line, what is the line coming in from the side?
#5
Member
Thread Starter
Join Date: Jul 2008
Location: canada
Posts: 334
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Furd
I was wrong assuming the 1 1/4'' line coming strait down was the drain and the
1 1/2'' line on the right was the vent It is the other way around
Thank you for pointing out that the vent should come strait down
I'm changing and moving the kitchen sink 24'' and thought of replacing the existing copper drain line as I'm also upgrading the supply lines.
Not sure if the 1 1/2'' drain line will be enough if in the future a dishwasher [ City By Law does not allow garburators ] is conected to that drain
I was wrong assuming the 1 1/4'' line coming strait down was the drain and the
1 1/2'' line on the right was the vent It is the other way around

Thank you for pointing out that the vent should come strait down
I'm changing and moving the kitchen sink 24'' and thought of replacing the existing copper drain line as I'm also upgrading the supply lines.
Not sure if the 1 1/2'' drain line will be enough if in the future a dishwasher [ City By Law does not allow garburators ] is conected to that drain