Is this project possible?


Newbie here. I have not done any arduino projects before. But if my inquiries below are possible, then I might as well dive into arduino.

Air conditioner problematic at times.

Project in mind:
Build a temperature detector.


  1. Is this possible?
  2. If the answer to #2 is yes, then is it possible to send an e-mail/SMS if the temperature reaches a certain heat level? (Heat level here should be defined)

As I said, I'm a newbie and have no broad ideas about doing projects in arduino. Any helpful input is appreciated. Thanks in advance.

Yes this is possible.
However it is not a beginners project get some experience first.

Hi, Get some experience, do some reading at http://ArduinoInfo.Info

Quite possible and not one of the hardest do to.
IMHO, difficulty level is about 4 (on a scale 1 [very easy] -10 [extremely hard]).

You'll have to make a few choices:

a) How will the temperature be measured?

  • Thermistor (analog)
    Very cheap, easy to program (if you have the formulae), very easy to build a circuit for, but it is also less precise than the digital methods

  • LM335 or similar (analog)
    precise, easy to circuit

  • LM35 (digital)
    very precise, but a bit harder to program, easy to circuit, more expensive

  • specialized IC, like DS1624 (digital)
    most precise, slow temp change, most expensive of these methods, a bit harder to circuit, but easier to program, since there are readily available libraries for it (I've published one here on the forums... check my sig)

  • there are certainly other methods, but these are the more common ones

b) How will you connect to the internet?

Your options are, basically, through ethernet ( $ ), wi-fi ($$) and 3G ($$$).

For everything you need to do (read temp, send e-mail, etc), there are probably code samples on the internet and possibly here are the forums. So your task might be resumed to build the circuit, put all the sample code together and test.

If you use the USB interface to connect the Arduino to a Windows PC then you can use Gobetwino to send the emails from the PC. In that case, the Arduino sketch can be very simple since it just has to read the temperature and print a command string to the serial port.

Certainly not especially difficult once you've done an arduino project or two. Be very cautious about hooking the SMS piece up though. It would be very easy for a bug or simple oversight to have your arduino sending thousands of messages - might get expensive. Test thoroughly!

Heres a question, where are you actually planning on putting the temp sensor? In the room near the conditioner, or are you gonna dismantle the AC and mount the sensor somewhere inside.
Also, in what way is your AC being problematic?

And last but not least, if possible, you shoudl try to avoid an SMS system. They work great, (and in some cases are a necessity like if your lo-jacking your car) but the shields themselves are expensive, and contracts or time-cards for the cell service can get expensive down the road. If your just putting the sensor somewhere in the room, best bet would be go with PeterH's method, and just send yourself emails about it.

Thank you all for your valuable ideas.

@PeterH: considered :wink:

@wildbill: i'm using a prepaid sim :slight_smile:

@Nikarus: inside the room. problematic in a way that it just turns off by itself sometimes. so i just want to be notified when this happens.

i can handle programming. the thing is, i don't know what kind of hardware i need:

  1. what kind of hardware should i use to detect the temperature?
  2. what kind of hardware should i use to send sms?

say, if the temperature > 37 degrees c, then it should be able to send an sms to me XD

i actually found a video here:


a. How will the temperature be measured? -- honestly i don't know yet what kind of hardware to use :~ ..
b. Between sms and e-mail, i prefer sms. so internet is not needed XD

btw, your work on homemade stackable shield is impressive.

a. How will the temperature be measured? -- honestly i don't know yet what kind of hardware to use :~ ..

Take a look at this:

btw, your work on homemade stackable shield is impressive.