Very basic plumbing DIY question

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Getting ready to replace a kitchen sink garbage disposal, and want to have everything on hand to avoid an extra trip to the store -- including new washer(s) for the P-trap.

I can't remember what it looked like last time, but from what I can gather now, since it's a metal trap, it calls for a square-cut rubber washer, and not the beveled plastic washers which are meant for PVC traps, correct?

Any reason to replace the nut if it's not chewed up?

Since it's a straight swap from one ISE to another, I figure I can keep the mounting and transfer the power cord.
 
One other thing to consider is that if you're going to keep the house for any substantial period of time you'll be replacing the disposer again. I'd look at replacing the hard wired electrical connection with a switched outlet under the sink (from the same feed/switch you are using now) and a standard plug to pigtail cable to provide power. This will allow you to unplug power when taking the old unit out, swap the cable (or replace as required) from the old unit to the new on your workbench, and then plug the new disposer into the outlet after the physical install.
 
No reason to replace the nut if it is not corroded. I think you are correct about the washer.

You are kidding yourself if you think you can get the job done with only one trip to the store, LOL. That's a guaranteed rule of DIY plumbing...3 trips back to the store on any plumbing project.
grin.gif
I usually take it apart before the store trip to unveil any unforeseen problems.
 
Originally Posted by mahansm
One other thing to consider is that if you're going to keep the house for any substantial period of time you'll be replacing the disposer again. I'd look at replacing the hard wired electrical connection with a switched outlet under the sink (from the same feed/switch you are using now) and a standard plug to pigtail cable to provide power. This will allow you to unplug power when taking the old unit out, swap the cable (or replace as required) from the old unit to the new on your workbench, and then plug the new disposer into the outlet after the physical install.


If you do that you will need a GFI outlet as it will be within 6' of the sink.
 
I've found that plastic is preferable for traps because, as previously mentioned, it won't corrode. I have seen connections to sinks that use the square washer. I generally get a bag of the rubber washers and pitch the polyethylene ones - the chances of getting a leak are greatly reduced.
 
I have never connected a dishwasher to the disposal. There is a special Y fitting for this. Figured the disposal might last longer.
 
Originally Posted by Donald
Originally Posted by mahansm
One other thing to consider is that if you're going to keep the house for any substantial period of time you'll be replacing the disposer again. I'd look at replacing the hard wired electrical connection with a switched outlet under the sink (from the same feed/switch you are using now) and a standard plug to pigtail cable to provide power. This will allow you to unplug power when taking the old unit out, swap the cable (or replace as required) from the old unit to the new on your workbench, and then plug the new disposer into the outlet after the physical install.


If you do that you will need a GFI outlet as it will be within 6' of the sink.


You don't need a GFCI if it is a dedicated outlet for a specific device like a garbage disposal. Only if it's a general purpose outlet. So add a single outlet instead of a duplex under the sink.

Also I wouldn't use PVC, they eventually leak from those plastic connectors. Metal is better, typically lasts longer. If not metal, black ABS and glue it.
 
Originally Posted by doitmyself
You are kidding yourself if you think you can get the job done with only one trip to the store, LOL. That's a guaranteed rule of DIY plumbing...3 trips back to the store on any plumbing project.
grin.gif
I usually take it apart before the store trip to unveil any unforeseen problems.

Ain't that the truth!! Been there, done that, and got the t-shirt.

Weekdays aren't too bad but weekday evenings and weekends at the hardware stores around here are a 30-45 minute wait standing in line to get in so minimizing trips is important.
 
I am not an electrician but my sister bought a new Condo last year and the site supervisor and was told the garbage disposal switch must be under the sink, that is inside the cabinet, and the wire must be armoured.
 
Originally Posted by JLawrence08648
I am not an electrician but my sister bought a new Condo last year and the site supervisor and was told the garbage disposal switch must be under the sink, that is inside the cabinet, and the wire must be armoured.


That might be local code or local authority decision. I see them on the wall next to the sink all the time.
 
Originally Posted by Wolf359
Originally Posted by JLawrence08648
I am not an electrician but my sister bought a new Condo last year and the site supervisor and was told the garbage disposal switch must be under the sink, that is inside the cabinet, and the wire must be armoured.


That might be local code or local authority decision. I see them on the wall next to the sink all the time.

Something like this can definitely vary by location unless the NEC requires it. As I understand it, NEC is the baseline and then local inspection authorities can impose stricter rules but not less strict rules.

I can understand spec'ing armored cable though. I've never seen a disposal that had the wiring neatly stapled up or anything. It's always just drooped from the 'box' to the disposal. Then you have people storing stuff in there, getting stuff in and out - armored cable makes sense. No point stapling it out of the way either as it would make disposal replacements trickier if the wiring ends up too short (junction box further away) or extra wire if it's closer.
 
Thank you, folks.

The trap appears to be solid, with no leaking, but I'll keep that in mind.

The cord will be an easy swap, because it's powered by a switched outlet, so I can yank it and do it on the bench.

I've generally had good luck with ISE, and need to replace them only because corrosion causes the turntable to seize up. This one has also developed a bad bearing, but it's probably 25 years old.

Hopefully, some level of quality still exists, but I wouldn't be surprised if it doesn't last as long, as with lots of stuff now.
 
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