First things first, here's a link to Leviton's 7299 combination switch & GFCI instruction sheet. For a tamper proof it will be a T7299. The only reason I give Leviton is because I know the part number. Hubbell, GE or Cooper are just as good and make the same.
GFCI protection for both outlets.
Follow the instructions that come with the GFCI. There are leads for the switch and lugs for the GFCI and also the feedthru-protection of another receptacle.
No GFCI outlet behind the dishwasher (for easy resetting without dishwasher removal).
This is accomplished by feeding the dishwasher receptacle using the GFCI feedthru-protection lugs.
The switch only toggling the garbage disposal outlet and not the dishwasher outlet.
This is accomplished by using the leads on the combo switch & GFCI to feed the garbage disposal.
Am I going to need to run some more wire through the walls?
If there are no wires between the combo switch & GFCI then you will have to pull some romex between the two.
Should I investigate adding a GFCI breaker for that circuit?
The breaker will cost a lot more than the combo switch & GFCI. Also, if the GFCI trips then you have to go to the breaker to reset it. At least with the GFCI receptacle feeding your dishwasher receptacle, you will be closer.
What other solutions would achieve the same effect as listed above?
I think this is the way to go, so you don't have to pull your dishwasher out to reset the GFCI. The nice thing about this site is some of the people either can think out of the box or have faced this problem before.
Simply replacing the first receptacle in the group with a GFCI receptacle, will provide protection to the entire group (if wired properly).
GFCI Receptacle
Locate the feeders
WARNING:
This procedure should only be carried out by persons with the proper tools and knowledge. And should be carried out with extreme caution.
When you open up the box containing the first receptacle in the group, you're going to notice two cables enter the box. One cable brings power from the breaker/fuse box (feeder), and the other carries power to the remainder of the circuit. You'll have to figure out which cable is which, so you know how to connect the GFCI receptacle.
- Start by turning off the power at the breaker/fuse box.
- Disconnect the receptacle, and position all the wires so that they will not contact each other or anything else conductive.
- Turn the power back on.
- Using a multi-, voltage or non-contact meter determine which set of wires is which. The feed from the breaker/fuse box will have power, while the line going to the rest of the circuit will not.
- Mark the wires in some way, and turn the power back off.
WARNING:
If you got a voltage reading on more than one set of wires, STOP, do not follow the rest of these instructions. contact a local Electrician.
Connect the GFCI
On the GFCI receptacle you'll notice that one set of terminals is labeled "LINE", and the other is labeled "LOAD".
- Connect the wires from the cable you marked as being from the breaker/fuse box, to the terminals labeled "LINE" (Black to brass, white to silver, green/bare to green/ground and the box if it's metal).
- Connect the wires from the other cable to the terminals labeled "LOAD".
- Install the receptacle into the box.
- Turn the power on.
- Press the Reset button on the GFCI receptacle.
WARNING:
If the receptacle will not reset, the wiring is connected incorrectly, or contains a fault. Contact an Electrician to complete the job.
GFCI Breaker
Alternatively, you can install a GFCI breaker to protect the entire circuit.
WARNING:
This procedure should only be carried out by persons with the proper tools and knowledge. And should be carried out with extreme caution.
- Turn off the breaker.
- Remove the black wire from the terminal on the breaker.
- Locate the white "neutral" wire associated with the circuit (should originate from the same cable).
- Remove the white "neutral" wire from the neutral bus bar.
- Remove the breaker (Caution should be used not to touch the hot bus bar while the breaker is removed).
- Install the GFCI breaker.
- Connect the white wire from the GFCI breaker to the neutral bus bar.
- Connect the white "neutral" wire from the circuit to the GFCI breaker.
- Connect the black "hot" wire from the circuit to the GFCI breaker.
- Turn the breaker on.
WARNING:
If the breaker will not reset, the wiring is connected incorrectly, or contains a fault. Contact an Electrician to complete the job.
Test the GFCI
Once the GFCI device is installed, it should be tested at least once a month to insure it's functioning properly.
- Press the Test button.
- Press the Reset button.
If the GFCI will not reset, the GFCI is bad, the wiring is incorrect, or there is a fault. Correct any faults, and/or install a new GFCI device.
Best Answer
Yes you can.
(I see the OP was edited to include details and will retain the rest for the database)
Having the GFCI marked 20 Amp is so the one model can be used for either type of circuit. If you have a 20 Amp Circuit then there is no problem with using 15 Amp receptacles on the same run.
BUT
Having the receptacles is one thing. Having the wiring and circuit breaker to support 20 Amps is another matter.
Unless you have the 20 Amp breaker and proper wiring, you will want to limit the total current draw to 15 Amps.
PLUS,
Most 20 Amp circuits are dedicated for specific purposes. Most often there will only be one single outlet for a specific need like a computer rack or a dialysis machine.
In a GFCI situation like described here, the second outlet would most likely be very near to prevent causing the breaker to trip inadvertently. Example: Plugging in an electric heater. Something that has nothing to do with the original reason a 20 Amp circuit was installed.
ALL THAT BEING SAID,
Yes, you can have either or both kinds of outlets on the same circuit, and it will work well unless you exceed the amperage allowed by the circuit breaker.