Rewiring Half-Hot Outlet with no Dedicated Hot Line

[TromboneAl]

Related to the mini-tank water heater installation, I now need to rewire the outlet under the sink to have one plug switched and one plug constantly on.

Unfortunately, the wiring was done like this,

and not like this:

As a result, there is no "always on" hot lead at the outlet.

So, I guess that some new wires will need to be run through the wall, and that I should hire an electrician to do this.

Note that the dishwasher doesn't plug in, but has a dedicated wire that disappears behind the cabinets.

An alternative is to dump the garbage disposal, since we rarely use it (we have a septic tank).

Thoughts?

 

[bjorn2bwild]

Could you run a short extension cord to the dishwasher outlet?

 

[samclem]

Yes, the right answer is to pull new wire to that location.

One "very hillbilly" answer is to make one outlet permanently live (by just connecting the black wires that are now switched) and add a switch under the sink for the disposal to control that outlet. Run the wires in conduit inside the cabinet to a surface-mount box just inside the cabinet door. Protect everything with a GFCI outlet or CB.

It wouldn't be very convenient (opening the door and feeling for the switch with wet hands), but if you want to avoid the trouble and expense of pulling wires inside the wall, it would work.

I wouldn't go as "cheap" as to use a wireless switch or a switched extension cord for the disposal. You want very positive control over something as potentially dangerous as a garbage disposal.

 

[REWahoo]

Could you run a short extension cord to the dishwasher outlet?

+1

If you rarely use the garbage disposal you could get an extension with an in-line switch and use this to turn the disposal on/off whenever you do need it.

Edit to add: X-posted with Samclem. Obviously I adhere to the "cheap" side on the International Scale of Frugality.

 

[NW-Bound]

I have gotten rid of our garbage disposer. Less grease and food scrap going down the drain to clog it up, less Drano to buy, fewer calls to the plumber. YMMV, of course.

 

[TromboneAl]

Called an electrician, and the rough estimate he gave me was $400.

You cheap hillbillies pointed me in the right direction. With something like this, you wouldn't need to reach under the sink:

Amazon.com: Etekcity® Wireless Controlled Electrical Light Switch Socket Outlet with Remote (Battery Included) ZAP 1F: Electronics

 

[NW-Bound]

But, but, but...

I wouldn't go as "cheap" as to use a wireless switch or a switched extension cord for the disposal. You want very positive control over something as potentially dangerous as a garbage disposal.

 

[TromboneAl]

Even better, I realized I had one of those remotes, I hooked it in and it works perfectly (yes it works for appliances as well as lights).

 

[samclem]

Edit to add: X-posted with Samclem. Obviously I adhere to the "cheap" side on the International Scale of Frugality.

Of course, when I said "cheap" I meant "alternate, less formal wiring standards."

Al, if you are going that route be sure to check the rating on that wireless switch to assure it's up to the task (same amperage/wattage as the garbage disposal).

 

[TromboneAl]

I wouldn't go as "cheap" as to use a wireless switch or a switched extension cord for the disposal. You want very positive control over something as potentially dangerous as a garbage disposal.

Oops, I missed that.

Yes, that's a consideration. If it went on when you are fishing around for something, it would be pretty bad (see Stephen Spielberg's Firestarter).

That would be pretty unlikely, of course, and IF you always turned off the wall switch to the disposal (and water heater) whenever you put you hand in, it would be even more unlikely. Or you never put your hand in...

Hmmm.

 

[TromboneAl]

Al, if you are going that route be sure to check the rating on that wireless switch to assure it's up to the task (same amperage/wattage as the garbage disposal).

Right. The disposal is 6 Amps and the switch is rated up to 12.

It's a neat solution, but since I don't use the GD much, I think I'll just leave it unplugged. If something gets in there, I can always reach under the sink and plug it in for a minute.

Too bad, because it's surprisingly fun to click the wireless remote and have the GD go on. I think humans have an instinctual affinity for action at a distance, related to the development of hunting tools such as the bow and arrow.

 

[samclem]

It's a neat solution, but since I don't use the GD much, I think I'll just leave it unplugged. If something gets in there, I can always reach under the sink and plug it in for a minute.

Your undersink storage approach must be a lot different from ours. I'd need to tie a rope around my waist so DW could pull me out if I wanted to reach the back for something.

 

[ERD50]

What does it take to pull another wire? We have conduit here, so it's not that hard.

I would not use the remote. I expect it is against code, which I'm pretty sure calls for a switch within X feet of the disposal, for safety reasons. The remote will end up under the cushion of the couch, several rooms away.

Ideally, you would pull that extra wire, and then use a three-way switch, one leg to disposal, one leg to WH. That way, when the disposal is on, the WH is off. Your 6 amp disposal and WH might exceed the breaker rating. Is the DW on that same breaker?

-ERD50

 

[travelover]

I'd pull in a 14/3 wire if it is easy, to make half of the outlet switched and half live. If not easy, I'd go with the under cabinet switch like samclem suggested. You could use a weather proof switch / box if wet hands are a concern.

Greenfield Weatherproof Electrical Box Lever Switch Cover with Single Pole Switch - Gray-KDL1P at The Home Depot

 

[TromboneAl]

What does it take to pull another wire? We have conduit here, so it's not that hard.

It would be a major deal here. No conduit that I know of.

I would not use the remote. I expect it is against code, which I'm pretty sure calls for a switch within X feet of the disposal, for safety reasons. The remote will end up under the cushion of the couch, several rooms away.
-ERD50

IF I did it, I would velcro or otherwise attach the remote to the wall near the existing GD switch. Statistic: 6% or lost remotes are found in the refrigerator.

Ideally, you would pull that extra wire, and then use a three-way switch, one leg to disposal, one leg to WH. That way, when the disposal is on, the WH is off. Your 6 amp disposal and WH might exceed the breaker rating. Is the DW on that same breaker?

Clever. But the WH is 10 amps. Add the 5 amp GD, and the total is less than the 20 SWD that the circuit breaker is rated for (some light switches are also on that circuit).

Are there any other risks involved in adding the remote?

 

[rbmrtn]

14-3 wire was mentioned. Run that from the switch to the outlet. There is a diagram at the bottom of this link, Switched Outlet To Half-switched - Electrical - DIY Chatroom - DIY Home Improvement Forum

 

[NW-Bound]

Problem with running wire is it may involve tearing out the sheet rock then patching it in order to thread the wire through holes drilled in 2x4 studs. There's no conduit used in new homes anymore.

 

[MooreBonds]

Clever. But the WH is 10 amps. Add the 5 amp GD, and the total is less than the 20 SWD that the circuit breaker is rated for (some light switches are also on that circuit).

2 comments on this:

1) NEC requires you to use breakers at 80% of the connected load. That means a 20 Amp breaker should have no more than 16 Amps connected.

2) Don't forget that motor start-up load is not the same as 'average load'. For an example, look at an In-Sink-Erator disposal:

InSinkErator | Badger® 5 | Garbage Disposal Repair

You'll note that it lists the load as "average" load. When an electrical motor first starts up, it draws more current than when after it's running. This surge is often noted as a "start-up draw" or similar wording, provided in the electrical requirements for motors.

So, if you serve the disposal and heater on the same circuit, don't be surprised if it ends up tripping on a regular basis due to the disposal's start-up draw (you'll likely be using the sink with hot water when you turn on the disposal - which would also cause the water heater to kick on). Add in some lights, and before you know it, you can easily exceed the breaker size, depending on how large the start-up current is for the disposal.

 

[NW-Bound]

If a 14/3 wire can be threaded through, then a 3-way switch can be used to make sure that both cannot be turned on at the same time, as described earlier.

...
Ideally, you would pull that extra wire, and then use a three-way switch, one leg to disposal, one leg to WH. That way, when the disposal is on, the WH is off. Your 6 amp disposal and WH might exceed the breaker rating.

 

[samclem]

Are there any other risks involved in adding the remote?

This isn't the normal thing that is controlled by these temporary wireless switches (a table lamp, etc). If it gets turned on while you are away from the house (RF interference, neighbor on the same freq, etc) the garbage disposal could be running (without water) for a long time. Probably until something starts to smoke.

If the switch works like one I have, there's no distinct "code" for "on" and "off." When the outlet gets a signal, it just changes state. So, in this case, the GD would be "off" 99.99% of the time and any valid signal it received would turn it to "on."

Also: the motor of the GD is fairly close to the receiver. I don't know how well it is shielded and you'd have to experiment a bit (different motor RPMs, etc) to be sure that once the motor is turned on the receiver can still reliably receive the "off" signal from the transmitter over the electronic racket.

 

[NW-Bound]

I myself have not experienced problems with wireless remote controls such as garage door openers, but interference problems do exist. I remember that a few years ago, my sister-in-law in south of San Diego complained about her garage door having a tendency to open itself, and that the Navy base there had something to do with it.

So, just now I searched the Web and found that indeed the US Navy was the culprit.

Garage door remote controls working again | UTSanDiego.com

 

[ERD50]

Problem with running wire is it may involve tearing out the sheet rock then patching it in order to thread the wire through holes drilled in 2x4 studs. There's no conduit used in new homes anymore.

Actually, conduit is still the norm in Chicago-land. I've seen it all my life, so I need to adjust when talking about wiring with people outside this area. There might be a few other places that require it, but they are few and far between.

It certainly has advantages - not sure they are worth the cost, but I'd guess the unions pushed for it. I think PVC drains are still verboten in Chicago-proper, plumbers union fights them.

2 comments on this:

1) NEC requires you to use breakers at 80% of the connected load. That means a 20 Amp breaker should have no more than 16 Amps connected. ...

Everything you say is true, but in practice breakers can be in an over-current condition for some time (tens to hundreds of seconds, IIRC) before tripping. The specs are pretty loose.

A GD might be run for 30 seconds or so. So that might trip the breaker if the WH is on at the same time. Probably not, but you'd most likely be aware of it when the GD shuts down. And the worst thing would be waiting for hot water until you reset the breaker, so not much downside. But if it happens often, breakers get more sensitive after each actuation, so the problem would get worse over time.

-ERD50

 

[scrinch]

I got rid of the garbage disposal and replaced it with a deep strainer basket in the sink drain.

 

[samclem]

Actually, conduit is still the norm in Chicago-land. I've seen it all my life, so I need to adjust when talking about wiring with people outside this area. There might be a few other places that require it, but they are few and far between.

It certainly has advantages - not sure they are worth the cost, but I'd guess the unions pushed for it. I think PVC drains are still verboten in Chicago-proper, plumbers union fights them.
-ERD50

Was/is there a similar prohibition against solid wire? I thought I'd read that local code in Chicago required stranded wire up to a fairly high gauge (10?). Stranded is more expensive, easier to pull, but requires care when terminating around screws/etc to assure no strands are left loose to cause a short circuit.

 

[ERD50]

Was/is there a similar prohibition against solid wire? I thought I'd read that local code in Chicago required stranded wire up to a fairly high gauge (10?). Stranded is more expensive, easier to pull, but requires care when terminating around screws/etc to assure no strands are left loose to cause a short circuit.

Not that I'm aware of. I have solid in my suburban homes, and I'm pretty sure that is used in the city.

-ERD50