Questions on replacing shutoff valve under sink

[JasonM]

I am planning to replace the 2 old shutoff valves under sink(as shown below) with the quarter turn shut off valve by BassCraft and its supply lines.



May I ask 2 questions regarding this?

1. The 2 shutoff valves are behind the sink drain pipes. Is it usually doable to replace the shutoff valves behind this drain pipe? Just in case the drain pipe needs to be cut out temporarily, where should it be cut for easiest reattachment?

2. Is the copper supply line that I pointed in the photo reusable? If so, how long will it last? I think it is at least 40 years old. Is it better to replace it with this
3/8 in. Compression x 1/2 in. FIP x 36 in. Braided Polymer Faucet Connector
by BrassCraft

Thank you very much.

 

[Reach4]

1. The 2 shutoff valves are behind the sink drain pipes. Is it usually doable to replace the shutoff valves behind this drain pipe? Just in case the drain pipe needs to be cut out temporarily, where should it be cut for easiest reattachment?

1. I would be looking to put a trap adapter on the end of the cut pipe. Then switch to a slip joint trap. Access becomes easy. I would be looking for some kind of hanger on the pipe to take the vertical load.

2. Is the copper supply line that I pointed in the photo reusable? If so, how long will it last? I think it is at least 40 years old. Is it better to replace it with this

Yes. Another 40-- or at least longer than a new braided line, I would think.

Now to reuse, do you keep the old nut and ferrule, and use those with the new valve body? You could try that.

I am not a pro.

 

[Sponsor]

 

[Mr tee]

The valves you have and their corrugated supplies are garbage. Change them. The compression nuts on the valves may or may not be standard 5/8" compression (aka 1/2" nominal). If they are standard you could reuse the existing nut and sleeve and throw the ones that come with the new valves in your junk drawer. Otherwise, the nut side will be 1/2 IPS and you will need to either remove them or hunt down a special adapter that fits the nut while the other end takes a standard 1/2" IPS angle stop. There is no reason to mess with the drain unless it is a PIA to work around it.

 

[JasonM]

1. I would be looking to put a trap adapter on the end of the cut pipe. Then switch to a slip joint trap. Access becomes easy. I would be looking for some kind of hanger on the pipe to take the vertical load.

Yes. Another 40-- or at least longer than a new braided line, I would think.

Now to reuse, do you keep the old nut and ferrule, and use those with the new valve body? You could try that.

I am not a pro.

Thank you Reach4 very much for the reply.
Could you elaborate on

put a trap adapter on the end of the cut pipe. Then switch to a slip joint trap

with some photo links?
Since I am not familiar with the drain pipes, I do not know what and how to do.

So, you think the copper pipe that I pointed in the photo is better and last longer than the Basscraft bradid 36" hose. I will see if I can connect and reuse it. I am replacing the old faucet with the new one, and that is why I am doing this.

Thank you very much.

 

[JasonM]

The valves you have and their corrugated supplies are garbage. Change them. The compression nuts on the valves may or may not be standard 5/8" compression (aka 1/2" nominal). If they are standard you could reuse the existing nut and sleeve and throw the ones that come with the new valves in your junk drawer. Otherwise, the nut side will be 1/2 IPS and you will need to either remove them or hunt down a special adapter that fits the nut while the other end takes a standard 1/2" IPS angle stop. There is no reason to mess with the drain unless it is a PIA to work around it.

Thank you Mr tee very much for the reply.

I learned in this forum that Terry strongly oppose using this corrugated stop. So, I am replacing it with the Basscraft quarter turn angle valve. I will see if the copper connection pipe fits this quarter turn angle valve. If it does not fit, I will temporarily use the 36" faucet supply line and buy the adapter later to reuse the copper connection pipe. So, you think the shutoff valve can be replaced with the drain pipe removed? I am preparing for the possibility in case the drain pipe makes it very difficult in replacing the shutoff valves. By the way, what is the PIA?

Thank you very much.

 

[Reach4]

with some photo links?
Since I am not familiar with the drain pipes, I do not know what and how to do.

https://www.homedepot.com/p/NIBCO-1-1-2-in-ABS-DWV-Hub-x-SJ-Trap-Adapter-C58017HD112/100344620

You cut the ABS pipe at an appropriate place, and glue on a trap adapter on the end of the pipe. The appropriate place is close enough to the sink for the p-trap to reach, and far enough to give you the access you need.

That then accepts a slip-joint p-trap.

Those are easily adjustable, and removable for cleaning etc.

However, if you cut far to the right to get access to your shutoffs, I think you would need an extension on the trap arm to reach the adapter. How far is it from the right cabinet wall to the output of the sink drain?

 

[JasonM]

https://www.homedepot.com/p/NIBCO-1-1-2-in-ABS-DWV-Hub-x-SJ-Trap-Adapter-C58017HD112/100344620

You cut the ABS pipe at an appropriate place, and glue on a trap adapter on the end of the pipe. The appropriate place is close enough to the sink for the p-trap to reach, and far enough to give you the access you need.

That then accepts a slip-joint p-trap.

Those are easily adjustable, and removable for cleaning etc.

However, if you cut far to the right to get access to your shutoffs, I think you would need an extension on the trap arm to reach the adapter. How far is it from the right cabinet wall to the output of the sink drain?

Thank you Reach4 very much for the reply.

Thanks to your explanation, I learned a little more on the ABS and PVC drain pipes, and I got the picture of what you are explaining.
If I cut to make enough space for the work, then I think there is a little bit of problem because of the drain pipe direction from the wall. I have to find the correct angle connector due to the bend of the drain pipe in the middle. Ideally, the cut needs to be made at about 14" or 15" from the p trap or 5" or 6" from the wall as the photo shown below. Is it possible to make the slip joint connection on the ABS drain pipe as I shown in the photo? Then, it would be easier for me to disconnect and reconnect for the shutoff valve work.

Is ABS pipe really 1 1/2" diameter pipe as shown on the pipe? To me, it looks bigger than 1 1/2" pipe.

Thank you very much.

 

[Reach4]

You may need to add an angle. A straight line has to come within about 3 inches of the center of the drain. If that is not going to happen, you need an angle.

A bend could be glued on downstream of the trap adapter (available 45 and 22.5 degrees) https://www.homedepot.com/p/1-1-2-in-ABS-DWV-22-1-2-Degree-Spigot-x-Hub-Elbow-C58082HD112/100346625, or you could use one of these upstream of the trap adapter.

When you glue, the stuff you glue will be ABS. But upstream of the trap adapter, you can mix materials. You could have chrome plated brass mixed with plastic.

 

[wwhitney]

Is ABS pipe really 1 1/2" diameter pipe as shown on the pipe? To me, it looks bigger than 1 1/2" pipe.

ABS DWV is sized as Schedule 40 pipe. That means it's ID is around 1-1/2" (actually 1.61"), and it's OD is 1.90". In contrast 1-1/2" tubular is 1-1/2" OD.

Cheers, Wayne

 

[JasonM]

You may need to add an angle. A straight line has to come within about 3 inches of the center of the drain. If that is not going to happen, you need an angle.

A bend could be glued on downstream of the trap adapter (available 45 and 22.5 degrees) https://www.homedepot.com/p/1-1-2-in-ABS-DWV-22-1-2-Degree-Spigot-x-Hub-Elbow-C58082HD112/100346625, or you could use one of these upstream of the trap adapter.

When you glue, the stuff you glue will be ABS. But upstream of the trap adapter, you can mix materials. You could have chrome plated brass mixed with plastic.

Thank you Reach4 very much for the comments. Happy Holidays.

Could you explain what is the downstream of the trap adapter and upstream of the trap adapter?
Also, if I cut where is the best place to cut on the drain pipe? Is the white line that I put on the photo a good place to cut for easy reattachment?

Thank you very much.

 

[wwhitney]

Downstream/upstream is relative to the flow of wastewater.

So upstream is the sink side of the trap adapter. Materials and joints are tubular and slip joints.

Downstream is the other side of the trap adapter. Materials and joints are ABS (in your case) and solvent weld.

Cheers, Wayne

 

[JasonM]

ABS DWV is sized as Schedule 40 pipe. That means it's ID is around 1-1/2" (actually 1.61"), and it's OD is 1.90". In contrast 1-1/2" tubular is 1-1/2" OD.

Cheers, Wayne

Thank you wwhitney very much for the comments. Happy Holidays.

I learned a new terminology. I did not know that there is a term Schedule 40 pipe.
How do you connect the regular 1.5" or 1.25" p trap drain white pvc pipe to this ABS 1.5 pipe? According to your explanation, this is connecting ABS's ID around 1-1/2" (actually 1.61", and it's OD is 1.90" ) with PVC 1-1/2" tubular with 1-1/2" OD. Could you point to a photo of the part?

Thank you very much.

 

[Reach4]

If I said either "the trap is before the trap adapter", or "the trap adapter is before the trap", would either statement seem weird? Those can be ambiguous I think.

Upstream or downstream should not be ambiguous for lines that carry drainage.

Could you point to a photo of the part?

The part? The part that connects 1-1/2 schedule 40 ABS with 1-1/2 tubular is the trap adapter, pictured in #6.

 

[wwhitney]

The part? The part that connects 1-1/2 schedule 40 ABS with 1-1/2 tubular is the trap adapter, pictured in #6.

And on your existing install, the trap adapter is the fitting where the vertical silver pipe connects to the vertical black pipe. You have a Schedule 40 union trap, rather than a tubular trap.

Cheers, Wayne

 

[Reach4]

The green lines represent the current path.
The blue lines represent a path with a new 22.5 bend with a new trap adapter.
The red line represents putting a new trap adapter at place A, and coming across with a long trap arm.

There is something called a "slip joint waste arm", and I suspect that can hook to the U of a slip joint trap. The waste arm is available in lengths up to 24 inches in brass

and up to 15 inch in plastic.

If the waste arm cannot connect to a trap, then an extension could be used on a shorter trap arm.

My top view sketch is not to scale. You would make your plans to match reality and available parts.

 

[JasonM]

Downstream/upstream is relative to the flow of wastewater.

So upstream is the sink side of the trap adapter. Materials and joints are tubular and slip joints.

Downstream is the other side of the trap adapter. Materials and joints are ABS (in your case) and solvent weld.

Cheers, Wayne

Thank you wwhitney very much for the explanation.

Please pardon my poor English. When I first read the word upstream, downstream, I though how the drain flow could flow up(upstream) in general. I thought it flows down(downstream). Now, I understand that the word up and down is like uptown and downtown or upstairs and downstairs, ie. the location.
Thanks to your explanation, I can understand what Reach4 said better.

Thank you.

 

[JasonM]

[QUOTE The part? The part that connects 1-1/2 schedule 40 ABS with 1-1/2 tubular is the trap adapter, pictured in #6.[/QUOTE]

Thank you Reach4 very much for the reply, and please pardon my poor English.
Now, I understand better. It confused me before.

Also, I see the photo in #6. If I use that adapater, I think I have to find the PVC 1 1/4" or 1 1/2" pipe 22.5 degree bend in order to make it exactly the same as it is now as shown in my first post photos. Is this correct?

Thank you.

 

[JasonM]

And on your existing install, the trap adapter is the fitting where the vertical silver pipe connects to the vertical black pipe. You have a Schedule 40 union trap, rather than a tubular trap.

Cheers, Wayne

Thank you wwhitney very much for the comments.
Now, I understand better and clearly that my existing P trap is ABS p trap, and it is different from the PVC p trap.
Thank you very much.

 

[JasonM]

View attachment 69242
The green lines represent the current path.
The blue lines represent a path with a new 22.5 bend with a new trap adapter.
The red line represents putting a new trap adapter at place A, and coming across with a long trap arm.

There is something called a "slip joint waste arm", and I suspect that can hook to the U of a slip joint trap. The waste arm is available in lengths up to 24 inches in brass

and up to 15 inch in plastic.

If the waste arm cannot connect to a trap, then an extension could be used on a shorter trap arm.

My top view sketch is not to scale. You would make your plans to match reality and available parts.

Thank you Reach4 very much for the reply.

I now see clearly what your original suggestion meant by this diagram. Although if the cut is made at A in your diagram, then it would be ideal with no bend in the middle, I would like to make a cut at B location because I feel more comfortable with room for error or screw-up. I feel that if I cut at A location, and if I do not do things right, then I am in a bind. Please understand that I never cut or joined ABS pipes before.

So, if I cut at B and find a tubular PVC 22.5 degree bend, will this be workable and a good solution? I need to examine the area more closely.

Thank you very much.

 

[wwhitney]

FWIW, tubular plastic is typically polypropylene, not PVC or ABS, but the material doesn't matter, since the joint is a compression joint on the outside of the tube.

I don't know if you're going to find a tubular 22.5 degree bend. So if you want a 22.5 degree bend, the best bet if you need to cut the trap arm is to use a solvent weld ABS 22.5 degree bend, then a trap adapter.

The current trap is removable by undoing the black hub joint and the trap adapter, so you might see if that give you enough access.

Cheers, Wayne