Tag Archives: Temperature Control

The DIY Brewery Temperature Logger Project

One of the most important things in brewing beer is temperature control. Matter of fact, one of my fellow club members is very fond of saying, “Come back and talk to me about brewing great beer after you have temperature control in place, because If you don’t have temperature control, there is no way you can brew great beer.” And I have to agree he is right, temperature control plays an important part of the entire brewing process. Not only do you need temperature control during the mashing process, you also need it during the fermentation, lagering and storage processes.

As part of building my Electric Brew System I’m going to need to control the temperature of my mash and I want to be able to program a mash profile and let the system notify me of significant steps in the process. To manage temperature you have to monitor it, so I started out building my controller with baby steps.

First I wrote the simple things like the control interface and services and then I broke the various parts of the automation control into separate circuits that could be built and tested by themselves.

I started off with the temperature monitoring circuit. What I wanted to be able to do, was set the interval that the microcontroller would read the temperature sensor and then log that to a file on a SD Card that I could then use to display a graph of the temperature over time. The DIY Brewery Temperature Logger project is the result of that first phase of development. It is a Netduino Plus Project that provides a web-based temperature monitor.

This project has several parts:

CodingSmackdown.ControlInterface – A jQuery based website that is hosted on the Netduino Plus’ SD Card and served using the NeonMika.NETMF.Webserver. It provides a self updating view of the temperature history as well as a settings tab that allows you to change the logger’s settings as well as the Netduino’s Network settings.

CodingSmackdown.Services – A C# .NETMF Library that contains the various threading libraries to handle the NETBIOS Name Resolution, NTP Time Client and Temperature Logging. It also includes classes to handle accessing the various GPIO and Analog pins on the Netduino and other various base and support classes used by the project.

CodingSmackdown.TemperatureMonitor – A C# .NETMF Application that is responsible for loading up the various services at start time and provides classes that are used by the NeonMika.NETMF.Webserver to process jQuery requests sent by the web client.

JSONLib – A C# .NETMF Library used to format the various responses in JSON format for use by the web client. The original code was written by Wouter Huysentruit and can be found over at http://code.tinyclr.com

NeonMika.NETMF.Webserver – A C# .NETMF Library that provides the entire web server for the project. The original code was taken from the NeonMika.NETMF.Webserver project here on codeplex over at http://neonmikawebserver.codeplex.com This version was paired down specifically for this project and to meet the memory constraints of the Netduino platform. For the latest version please reference the original project.

Below are pictures of the user interface and schematics of the temperature sensor circuit, so you can build it yourself.

The main page retrieved by navigating to http://netduinoplus/index.html


The Settings Tab that can be used to change the Temperature Logger’s behavior and network settings


The breadboard layout of the temperature sensor circuit


The schematic of the temperature sensor circuit


Images of the prototype Netduino Shield that holds the temperature sensor circuitry




You can find the source code and updates to the project at http://diybrewerytemplogger.codeplex.com/

Till next time, stay sanitized and keep an eye on those fermentation temps and I’ll catch you for a pint around the keg.

Jim Lavin – Otaku Brewer

The Search for a Counter-Top Electric Brewing System

While I’m busy working on my full-scale all-electric brewing system, I figured it be nice to have a small counter-top electric brew system that I could use to continue brewing. I also thought it would be a good proto-type for the larger system I’m building.

While discussing the idea with a couple of folks from the North Texas Homebrewers Association, I came up with a couple of ideas:

  1. Use a couple of Electric Coffee Urns for the brewing vessels.
  2. Use an Electric Turkey Fryer for a simple Brew-in-a-Bag system.
  3. Scavenge the parts from an old commercial Coffee Maker I just have setting around.

I have a couple of goals that I want to meet:

  1. Keep the system small enough to fit on a counter top or kitchen table.
  2. Everything has to run off of a single 120 Volt AC Outlet.
  3. Has Temperature Control, so I can do step mashes.
  4. Big enough to brew at least a 2 Gallon batch at a time.
  5. Keep it as cheap as possible.

Using Electric Coffee Urns for the Brew System

To experiment with the first concept, I picked up a 40 Cup Electric Coffee Pot from my local Wal-Mart. This has just enough capacity to brew a 2 Gallon batch if I plan on making a three vessel system.


The coffee pot will hold a little over 7 quarts of water, which is just enough strike water to mash around 5 pounds of grain. However, I think this is pushing it a little, the 7 quarts of water only leaves about an inch of head space without adding the grains. So my feeling is to really do a full 2 Gallon batch a 50 Cup or larger Electric Coffee Pot is a must.

I also did a couple of tests to see how hot I could make the water and It pretty much tops out at around 175 Degrees F in a little under 30 minutes. Now this is not bad for a Hot Liquor Tank or Heated Mash Tun, but it will never be good enough for a boil kettle.  I pulled the bottom off the Coffee Pot and found what looks like a thermistor or temperature limiting resistor that cuts the power to the heating element. If I could find a way to bypass the thermistor, I’d probably be able to bring 2 Gallons of water to a boil. The 40 Cup unit has a 1000 Watt heating element, but I’ve looked at a couple of larger units that have 1500 Watt heating elements which should probably be more than enough power to bring 2 Gallons of wort of a boil.

Another issue I have with the Coffee Pot is that I still have to come up with a temperature control system that would allow me to control the temperature of all the vessels by interrupting the power to the heating element as the target temperature is reached. Now this is not a big issue, since this is one of the main components of my larger system that I want to build out and perfect before I spend a lot of money and find out that my design won’t work.

My last issue with the Coffee Pot is that I’ll need some sort of pump system or gravity feed structure to move the water from the Hot Liquor Tank to the Mash Tun to the Boil Kettle. This will add expense to the overall system which kind of goes against my last goal to keep things as cheap as possible.

The nice thing about the construction was that the spigot is attached to the pot using a metal nut around a half-inch in diameter which would make replacing the spigot with a more acceptable ball valve or bulk head fitting pretty easy.

Right now I’m estimating that the entire system will cost about $500 to build out fully with all the temperature control and miscellaneous components. So, until I’m fully convinced this is the way to go, I’m going to put the Electric Coffee Urn Brew System on hold and check out some of my other options.

Till then, keep an eye on those temps!