Should I tie a new dishwasher drain hose to an unused 1.5" drain stub or to the kitchen sink drain?

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Bosch sells a hardwire option. I installed two last week.
https://www.lowes.com/pd/Bosch-4-1-...VYM7CBB0XQg8eEAQYASABEgL6LPD_BwE&gclsrc=aw.ds
I Installed 3 insinkerator garbage disposals also that all had hardwire adapters in the box. Corded models are extra.
https://www.lowes.com/pd/Bosch-4-1-...VYM7CBB0XQg8eEAQYASABEgL6LPD_BwE&gclsrc=aw.ds
Yes, why yes they do! For an extra $20 that you may not know you needed...but the "hardwire" option on the Bosch differs greatly from other manufacturers as you probably know from your experience. With most dishwashers that feature a hardwire connection, the connection is made in some small box in the lower part of the dishwasher; bring your NM cable into the box, add the cable clamp or plastic ferrule and wire it to the wires there. In a Miele dishwasher I installed last week, it came pre-wired with a cord like my Bosch did. However, if you wanted to hardwire it, no additional parts needed; remove the cord and there was a little terminal inside a little J-Box in the dishwasher. Add your wires to the terminal points. For all the money my neighbors paid for the Miele it's not nearly as quiet as a Bosch.

So basically to hardwire a Bosch you bring their cord to a J-box. For many other brands they assume reality: there’s a length of NM cable coming from the floor or wall, and you bring that to the dishwasher’s own box. All good if you know that in advance, so you can have the required parts on hand.

I've installed many ISE disposals, but the LAST one I installed was different than the rest. There was some kind of proprietary plug device and whatever you needed to install it either hardwired or with a pigtail was included in the box. Nice.
 
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Anyone may laugh or joke about this, but a large number of home fires in the USA have been shown to be caused by electrical arcing.

The development of AFCI breakers and their implementation in code is the result of real world analysis by the National Fire Protection Association, a non-profit whose goal is education on fire prevention. The last data they've compiled is for the years 2015-2019, and it shows an average of 46,700 home fires each of those years caused by electrical failure or malfunction, 390 homeowner deaths, and 1,330 injuries. Electrical failures or malfunctions were the cause of 13% of home fires. Arcing served as the heat source in 63% of home fires that involved electricity.

Similarly there were and average of 32,160 home fires caused by electrical distribution and lighting equipment in those same years. Those caused 430 homeowner deaths, over 1,000 injuries. These most often originated in a bedroom.

So, assume a simple home, perhaps on the larger side, and the living and bedroom areas may have just six breakers serving these locations. That's six AFCI breakers costing about $250. The only tool needed to retrofit these to a panel is your brain and a screwdriver.

Considering how many crappy appliances made In China I see, as well as that infernal backwiring done by fast electricians, I'm sure as heck glad I have these AFCI protection devices. Cheap protection, even with the occasional nuisance trip.
 
I bought the inlet tee and installed it. I also got a torpedo level, and found that even though I got the drain pipe from p-trap to wall to the same angle it originally was at, it slopes a lot in the wrong direction for a foot. The cause is a few inches from the wall, there’s a 45 degree short elbow and half of it angles down, and is glued in. 1.5” of it has a good slope and 1.5” has a bad slope. Thus the 10” pipe from it to the p-trap had the same bad slope. Also, to get a proper slope, the p-trap would need to be 2/3” higher, and I’ve already made everything as short as possible.

I found a solution that isn’t perfect, but I can live with. The photo below shows it. I replaced the p-trap and 10” pipe with a Simple Drain p-trap that allows the p-trap to end much higher so there’s a good slope from it to the elbow. I know ribbed pipe tends to accrue gunk over time, but I put bio enzyme drain cleaners in a few times a year that eat away most organic material. I can also massage the ribs twice a year to further remove build-up. A benefit is I now have one piece where there used to be two. The 10” pipe was 20 years old, and thin, low quality.

Except for the ribbed pipe not being ideal, does the rest of this approach look ok? I haven’t attached it at either end. I’ll do that soon if the approach looks ok. The bottom of the p-trap is out of view, but will have the required 2”-4” space.

For the 1.5” of the elbow still having poor slope, which of these three options is best: A) Don’t worry about 1.5”, given 12” was poor slope for lots of years and it worked ok. B) Cut out the elbow and add a new one with good slope. C) Replace the elbow and also buy and attach a new 10” pipe to the elbow, so the length of the ribbed section would be far shorter. If I do option C, can I use this elbow Oatey 1-1/2 in. White 45° Plastic Double Slip-Joint Sink Drain Elbow Pipe HDC9665 - The Home Depot then cut off 6” of this Oatey 1-1/2 in. x 16 in. White Plastic Double Slip-Joint Sink Drain Tailpiece Extension Tube HDC9793E - The Home Depot and attach the cut straight end to the elbow, so I can have the male end needed for the Simple Drain connection? Here's how it looks now:

1706000617620.png

Here's a close-up of the elbow showing 1.5" of it sloping towards the p-trap. And a photo showing that after the first third, the elbow starts sloping correctly. The camera isn't quite level, and the angle changes somewhat, but I think it shows the situation well. I really appreciate the opinions. It's very helpful.

1706001459272.png1706001359075.png
 
Well there’s nothing plugged into it and I’m still saying it’s not required. I’d bet it’s switched and it’s also old existing work.

Meanwhile in the real world, we have every tank type electric water heater on the market have from 20-30 amps 240v connect with wire nuts on the top of the unit inside a metal bowl. With the entire case on the outside 2’ x 5’ pure metal.
I just replaced an electric water heater in the basement of our cottage. It was leaking at the top and the metal bowl you speak of was full of water. I killed the breaker before I went and looked at it thankfully, but that is pretty insane when you think about it.
 
Can’t really tell what I’m looking at but perhaps a mini-tankless or point of use water heater on a bathroom lavatory sink, with a 240V feed?

What did you fix there?
It’s a deadly dangerous condition…….

I thought you’d see that right away. Could you imagine if water leaked into that ???? Wow weee

I see it all the time, I work in old building and old houses. I also work in new building and new houses. You see things.
 
I just replaced an electric water heater in the basement of our cottage. It was leaking at the top and the metal bowl you speak of was full of water. I killed the breaker before I went and looked at it thankfully, but that is pretty insane when you think about it.
I get scared when I find things like that. What if ? Ya know ?
 
Look at this…….

Someone switched from electric to gas and just left the wire exposed with the switch in the off condition.

Found this last night at 9pm on emergency call out.
BA155D74-BCF7-4132-B937-E63F23773DAC.jpeg

So for safety sake it’s “ best practice “ to go ahead and arc fault and GFCI the entire house.

Isn’t your life worth it ?
 
Look at this…….

Someone switched from electric to gas and just left the wire exposed with the switch in the off condition.

Found this last night at 9pm on emergency call out.
View attachment 43933

So for safety sake it’s “ best practice “ to go ahead and arc fault and GFCI the entire house.

Isn’t your life worth it ?
They should tape the switch in the off position. ;)
 
They should tape the switch in the off position. ;)
I love it !!!

Yeah, believe me, I checked. The breaker to that 10ga 240v 30amp circuit was used for a new workshop and the water heater changed to gas. I flipped the switch and tested the wires, no power. So it’s disconnected but still not properly terminated IMO. The wire coming out of the wall should be in a sealed box. You could also make a good case it shouldn’t be sheathed romex and it should be in conduit. Safety first 😬
 
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I love it !!!

Yeah, believe me, I checked. The breaker to that 10ga 240v 30amp circuit was used for a new workshop and the water heater changed to gas. I flipped the switch and tested the wires, no power. So it’s disconnected but still not properly terminated IMO. The wire coming out of the wall should be in a sealed box. You could also make a good case it shouldn’t be sheathed romex and it should be in conduit. Safety first 😬
You are right even though you're laughing. Yes, NM/Romex unused, as you show, should not be dangling in air. It needs to be cut off, and terminated in a box. One without a hole in the cover.
If it were used, those darned "best practices" would have it in conduit or armored cable as you note.

Note also that the galvanized ceiling protector needs to be put back in place. That's a no-no too. Fire hazard.
 
I bought the inlet tee and installed it. I also got a torpedo level, and found that even though I got the drain pipe from p-trap to wall to the same angle it originally was at, it slopes a lot in the wrong direction for a foot. The cause is a few inches from the wall, there’s a 45 degree short elbow and half of it angles down, and is glued in. 1.5” of it has a good slope and 1.5” has a bad slope. Thus the 10” pipe from it to the p-trap had the same bad slope. Also, to get a proper slope, the p-trap would need to be 2/3” higher, and I’ve already made everything as short as possible.

I found a solution that isn’t perfect, but I can live with. The photo below shows it. I replaced the p-trap and 10” pipe with a Simple Drain p-trap that allows the p-trap to end much higher so there’s a good slope from it to the elbow. I know ribbed pipe tends to accrue gunk over time, but I put bio enzyme drain cleaners in a few times a year that eat away most organic material. I can also massage the ribs twice a year to further remove build-up. A benefit is I now have one piece where there used to be two. The 10” pipe was 20 years old, and thin, low quality.

Except for the ribbed pipe not being ideal, does the rest of this approach look ok? I haven’t attached it at either end. I’ll do that soon if the approach looks ok. The bottom of the p-trap is out of view, but will have the required 2”-4” space.

For the 1.5” of the elbow still having poor slope, which of these three options is best: A) Don’t worry about 1.5”, given 12” was poor slope for lots of years and it worked ok. B) Cut out the elbow and add a new one with good slope. C) Replace the elbow and also buy and attach a new 10” pipe to the elbow, so the length of the ribbed section would be far shorter. If I do option C, can I use this elbow Oatey 1-1/2 in. White 45° Plastic Double Slip-Joint Sink Drain Elbow Pipe HDC9665 - The Home Depot then cut off 6” of this Oatey 1-1/2 in. x 16 in. White Plastic Double Slip-Joint Sink Drain Tailpiece Extension Tube HDC9793E - The Home Depot and attach the cut straight end to the elbow, so I can have the male end needed for the Simple Drain connection? Here's how it looks now:

View attachment 43930

Here's a close-up of the elbow showing 1.5" of it sloping towards the p-trap. And a photo showing that after the first third, the elbow starts sloping correctly. The camera isn't quite level, and the angle changes somewhat, but I think it shows the situation well. I really appreciate the opinions. It's very helpful.

View attachment 43932View attachment 43931
I would not use that corrugated line as a P-trap. For the short distance you have, I wouldn't worry about it provided you can determine you have an air space from the trap weir to the vent connection inside the wall.

1706026649214.png
 
You are right even though you're laughing. Yes, NM/Romex unused, as you show, should not be dangling in air. It needs to be cut off, and terminated in a box. One without a hole in the cover.
If it were used, those darned "best practices" would have it in conduit or armored cable as you note.

Note also that the galvanized ceiling protector needs to be put back in place. That's a no-no too. Fire hazard.
the water heater is being replaced, that’s why the escutcheon is slipped down. I had to disconnect it last night because the gate valve failed. The tank is leaking.
 
Anyone may laugh or joke about this, but a large number of home fires in the USA have been shown to be caused by electrical arcing.

The development of AFCI breakers and their implementation in code is the result of real world analysis by the National Fire Protection Association, a non-profit whose goal is education on fire prevention. The last data they've compiled is for the years 2015-2019, and it shows an average of 46,700 home fires each of those years caused by electrical failure or malfunction, 390 homeowner deaths, and 1,330 injuries. Electrical failures or malfunctions were the cause of 13% of home fires. Arcing served as the heat source in 63% of home fires that involved electricity.

Similarly there were and average of 32,160 home fires caused by electrical distribution and lighting equipment in those same years. Those caused 430 homeowner deaths, over 1,000 injuries. These most often originated in a bedroom.

So, assume a simple home, perhaps on the larger side, and the living and bedroom areas may have just six breakers serving these locations. That's six AFCI breakers costing about $250. The only tool needed to retrofit these to a panel is your brain and a screwdriver.

Considering how many crappy appliances made In China I see, as well as that infernal backwiring done by fast electricians, I'm sure as heck glad I have these AFCI protection devices. Cheap protection, even with the occasional nuisance trip.
Have you heard of the Ting? I have one in my house, paid for by my insurance company. Really pretty cool.

https://www.tingfire.com/
 
MicEd69 said:
I would not use that corrugated line as a P-trap. For the short distance you have, I wouldn't worry about it provided you can determine you have an air space from the trap weir to the vent connection inside the wall.
Thanks. On one hand, I can't see the vent connection because the drain goes through a cut-out in the cabinet, then 1-2" of space, then it disappears into the concrete wall. On the other hand, I know that after the p-trap and weir line, the drain slopes upward for about 11", then downward for 8" to 10". I can see 5" of the downward slope before it enters the wall, and it's a mild slope.

If the wall is 10" thick and the vent connection is half-way through it, the total downward part is 10". With the upward 11" section and the visible downward section being a mild slope, I figure there's no way that the drain drops a whole 1.5" by when it's at the vent. Does that make sense - because if it doesn't, then it seems like I should probably go with the corrugated line for the p-trap to be safe?

Is the only purpose of that air space to keep foul air from entering the house? If yes, what if I use the sink and DW for two weeks and if no bad smell occurs, would that mean I'm almost certainly in the clear on that front? Or does the bad smell sometimes take several months to first happen?

If there's another purpose for that air space, what is it? I should factor that in too. Thanks so much!
 
The P-trap provides a liquid seal to keep sewer gases from coming up the drain line. Without it, there would be a clear path between the gases in the sewer and the fixture drain. If the slope of the drainpipe is too steep, or if the line is too far from the vent, some of that liquid seal can siphon down the drain. Then, either immediately, or after some period of time of non-use, the trap water can evaporate causing gases to come up the drainpipe. The IPC code uses straight geometry to establish the length between the P-trap weir and the vent line. At a 1/4" per foot slope, with a 1 1/2" pipe, their code distance is 1 1/2 divided by 1/4 or 6 feet. Other codes, like UPC, add a safety factor for imperfect installations and use 3 1/2 feet.

So, you could take the length dimensions you and slopes have and make a drawing showing what the liquid level would be based on your present geometry. Or with these shortish dimensions and slight slopes, install a proper P-trap and let the good times roll. Oops, you're in Florida not Louisianna, so I should have said let the sunshine in.
 
Thanks. I marked up the diagram you posted: the green circle shows where the height of the bottom of my drain is at when it enters the wall after about 12" up slope and 5" down slope. Net total there's no drop, and instead it’s 1/4” higher. Thus for it to drop 1 full pipe’s diameter from the trap outlet to the vent, it would have to drop 1.75" inside the wall in a span of just 3" to 5", which the red line shows:

1706170098129.png

I can't see if something that crazy exists in the wall, but I figure it doesn't because it was used like this for 10-20 years. But if it does exist, wouldn't it mean that it will likely be a problem no matter where I put the p-trap? If such craziness exists, the only thing I could do is lower the p-trap more, but then the upward slope for the first 1'of drain after the p-trap would be even steeper.

Speaking of which, here is a photo of the level bubble of that slope. I had assumed it was too steep of a slope, but I think you might be saying that this slope is fine if it's only 1' long ... and that having this upward slope is better than using the ribbed pipe with a good slope. Is that right? A lot of comments by people were posted, so I don't know if you saw this photo of the level bubble of the 1' upward slope between this elbow and the p-trap:

1706169839981.png
 
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This is what your installation will likely look like. The blue line is the trap water level. The upward slope of your trap arm will retain water and will be part of your water trap. If the dimensions of your slopes per foot are like 1/4" or 3/8", and it has been this way for 10-20 years, you likely won't have any problems unless you use the corrugated line as a P-trap.

1706193262864.png
 

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