How can I use an off-peak controller with my 240v air conditioner?

Question

My unit's window mount A/C unit is pictured. I am looking for a converter of some sort so I can use a utility supplied shutoff device.

The Unit itself does not have a temperature control or setting. Just on/off, high/low. The electric company provides the wifi plugs as a way to help control energy costs that connect to the AC unit, and I can control the temperature on my phone via wifi vs it just running all day long.

I cannot afford to run my AC all day, but have a pet and cannot leave it off all day. I am looking to attach one of those plugs that my electric company has to shut on and off when it reaches a certain temperature in the house. However, I don't know what this is and how to convert?

Answer 1

Here's a work-around.

1. Use the 110v smart switch to turn a normal phone USB charger on/off.
2. Get a USB heating pad for < $2, or if handy w/ solder, a 500 ohm usb-powered resistor.
3. now you can make a small space slightly warm (or not warm) via wifi
4. wrap the heater around the thermostat temp probe behind the air filter on the AC. You might have to remove the plastic faceplate, but you don't have to heavily mod the AC.
5. Set AC to 90F, or whatever a max temp in the room should be if wifi conks out.
6. To cool the room, turn on the wifi socket, which turns on the usb, which heats the thermostat.
7. To stop cooling the room, turn off outlet/usb, which allows the termostat to reach room temp in about 30 seconds, turning off the AC, since it's cooler than 90F.

Advantages: cheap, simple, electrically isolated from mains, no permement AC mod needed Disadvantages: slightly rube goldberg, small lag on on/off, short manual setup routine

Of course, you also need a way to get the temp to the smarts that turns the wifi switch on and off, but that's a different question. you can use node-red to setup a simple control loop based on temps and/or state over-rides, for when you're home on the weekend or whatever.

EDIT: based on comment If the AC has no thermostat, and you're used to plugging it and unplugging it to control it, you can adapt the above using a 5v 15A relay module instead of a heater to switch the A.C. to the AC on and off. You would power the relay with the USB charger that's being wifi controlled, and connect the relay switch terminals to a splice in the line. If you don't want to splice your landlord's cord (understandable), but an outlet ($5) and pigtail ($15) that fits the cord and splice that miniature "extension cable".

Answer 2

Your AC unit needs 240 volts to operate. While most houses in the US have 240V, most outlets are only wired for 120V. This is a limitation based on both the outlet itself and the wiring to it.

If you want to use this AC unit in a room without 240V, you need to have new, heavier wiring installed to that location.

You might consider a new small, energy efficient 120V unit. They often can be found for just over $100.

(All of this assumes you are in the US, or another country where 120V is standard.)

Answer 3

That's a NEMA 6-15R 250 Volt 15 Amp socket ( http://www.plugsocketmuseum.nl/NorthAm-3hd.html ).

Many utilities offer discount programs (for example "CoolCents"), where you get a discount but agree that during peak usage times, your AC may briefly be disconnected. These programs once relied on pager based shutoff devices, but they're moving to "internet of things" and wifi connected smart thermostats. Check with your utility company for details. That plug is NOT that uncommon, if a device is available, it should be OK available with that plug.

A plug converter, even if you made one, would not help you use this 240V unit with a 120V plug.

Consider sun shades, an attic fan, or other passive or less costly methods to keep the temperature down. Window AC units are not that efficient, especially if sun shines directly on the coils on the outside of the building. YOU CAN DO MORE WITH SIMPLE CONSERVATION THAN FANCY ELECTRONICS.

Consider just turning the temperature dial to the highest possible temperature. The device will run only as much as needed to get to that set point. The A/C does not use energy when the temperature is above the set point.