A First Look At My Arduino BBQ Thermometer

I’ve uploaded a first look at the Arduino powered BBQ thermometer and software that I’m building. It’s using an Arduino Uno with Ethernet shield

The probe is a 100K “meat probe” (aka “thermistor”) that I took from a store bought meat thermometer. Something like this replacement probe would work great. It’s a bit of a guessing game as to wether the probe is a 10k or 100k Ohm probe. I tried 10, 100, 1k, 10k and finally 100k resistors in my thermistor setup. You can read about thermistor setup on the Arduino playground, and at Hacktronics.

The Arduino code produces a JSON document when I make an HTTP request to it. The software is built with Kendo UI Mobile, and reads the JSON document on a 1 second interval.

I’ll be blogging about this more, and hopefully soon, with plans on going through a step by step “how I learned” series – at least, that’s the plan. For now, this little teaser video should give you a good idea of what can be done with an Arduino, some simple parts from a store, and a mobile app framework like Kendo UI Mobile. :)

… I need to learn how to optimize my C code for battery life. I’ve run that 9volt battery maybe 10 or 20 minutes, total, and it’s already dead. :P

About Derick Bailey

Derick Bailey is an entrepreneur, problem solver (and creator? :P ), software developer, screecaster, writer, blogger, speaker and technology leader in central Texas (north of Austin). He runs SignalLeaf.com - the amazingly awesome podcast audio hosting service that everyone should be using, and WatchMeCode.net where he throws down the JavaScript gauntlets to get you up to speed. He has been a professional software developer since the late 90's, and has been writing code since the late 80's. Find me on twitter: @derickbailey, @mutedsolutions, @backbonejsclass Find me on the web: SignalLeaf, WatchMeCode, Kendo UI blog, MarionetteJS, My Github profile, On Google+.
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  • Matt Polichette

    This is great… I was brewing with a friend on a cold day recently and we were talking about how it would be cool to have a remote thermometer which could signal us when the wort is close to boiling. That way we wouldn’t have to hang out outside where we could hear our normal thermometer start beeping.

    Keep doing cool stuff Derick, I really enjoy your articles.

    • Chris B

      Arduino is like a treasure trove for brew hardware. I would love to build my own dual-stage fermentation temp controller (ideally w/ the ability to send data to a server about when the heat/cool side turned on, length of run, etc..), temp controlled mash tun (kick the fire on when the temp gets below x, cut off when y is reached), automatically pump from hot liquor tank to lauter tun to boil kettle…with enough time/money you can automate the entire process. I know you can buy systems ready made for that, but it’s a lot more fun to build your own.

      Unfortunately, fear of destroying expensive equipment and burning down my house have scared me off thus far. I know enough about electricity and fire to know that I am not qualified to automate either.

    • that is almost exactly what i built this for! except i built it for BBQ, not beer. but the reason is the same :)

      i have a remote BBQ thermometer that requires me to be less than 20 feet away from it… what’s the point of that? and then I thought about having this phone that can do mobile apps and web apps and get text messages… so why not make a thermometer that works the way i want? :D

  • Greg Asman

    This looks great. I destroyed my stoker (got it wet) and now want to make a better version. Have you tried getting a blower working with it?

    • no, i have a pretty fancy smoker that handles all of that for me (all electronic, etc). so my thermometer is just a thermometer. i do know that other people have built entire blower / fire assemblies with arduino, though. it’s definitely possible. just have to get the right hardware.


    Couple of questions….and thanks in advance for reading. I am brand new to Aduino, and looking to build a temp control with fan/wifi device that will connect to server allowing control through a mobile app (just for fun).

    1) Where did you get the input connector for your thermometer?

    2) Can the Adurino Uno handle a total of 4 thermometer readers?

    3) I was looking at the fan control by temp (http://www.barnesian.com/arduino-powered-smart-fan-controller/) Can the Aduirno Uno handle 4 probes and a single fan?

    4) There are a few wifi boards….how do I know which one I need for my first build?

    • Hi!

      1) I bought them at RadioShack: http://www.radioshack.com/product/index.jsp?productId=2103450 – any 3/32″ audio input jack will work. If you buy a stereo input jack, like i did, just clip off the 3rd connector. You don’t need it.

      2) yes – each thermistor (thermal resistor – the thermometer probe) will use 1 analog input. you have 5 analog inputs on an Uno.

      3) see #2 :)

      4) avoid the Arduino Wifi Shield. it’s garbage. I wasted $200 on two of them. utter garbage. Other than that, just pick something that looks like it supports what you need. I love my WiFly module with SparkFun’s XBee Explorer Regulated. It’s a great setup for hardware, and cheap. Requires more C/C++ than I’m used to, to write WiFi code, but that can be learned. If you want all-in-one (wifi and arduino), check out Arduino Yun or Spark Devices.