Like many others, I started home beer brewing using the extract method. I had a boil kettle, a burner, and a thermometer. It really was as simple as it gets. After brewing for several years using this method, I became bored with the recipes. I wanted somthing more challenging and wanted to move into all grain. As I moved into All Grain, I relized the importance of temperature control. It is important with extracts, too, but very important in the all grain process. After all, mash temperature can control the outcome of your beer by making it dry and thing or less fermentable and sweeter.
This article covers how to regulate your mash through temperature control. I have broken this article down into four sections. Chosing your Controller, Electricity, Gas Valve, and Temperature probe. Controlling your tempature will take, at a minimum, a gas valve, controller, and temperature probe.
Controller - I discuss temperature controllers first simply because it will outline what type of electricty you end up with.
Will you be designing a 24 volt system with relays or a straight 120 volt system. Two of the easist to operate controllers are the LOVE Control and Ranco Digital Temperature Controller. Out of the two controllers, I prefer the LOVE because the digital readout is large and bright. The downside is that you most likely will need to build some sort of enclosure. I built a simple enclosure for a fermentation control (see link – http://www.gbrewing.com/2009/10/14/fermentation-temperature-control/ ) The Ranco is self enclosed and easy to operate. If it had a larger digital display, I would prefer the Ranco.
If you want a more advanced system, you can look towards the BCS-460 Temperature Control System by Embedded Control Concepts. I have written numerous topics about this system scattered throughout this website. Based on a web based user interface, this system allows you to control the temperature as a PID (proportional–integral–derivative), turns pumps on and off, etc. As a stock unit, you can have up to four seperature temperature inputs, six outputs to control items such as gas valves and pumps, and four DIN inputs such as push button or float switches. I would consider this to be a higher end controller for people who want to create an extreme brewing system. It takes a higher level of knowledge , time, and money to create a system using the BCS-460.
The BrewTroller is also an option. BrewTroller is an open source standalone brewing control system based on the Sanquino Platform. The BrewTroller is for the extreme DIY’er. You would be “building” your own brew controller using electronic components from the ground up.
Here’s quick overview of BrewTroller features:
- (4) PID or On/Off controlled heat outputs (HLT, Mash, Kettle and Steam Heat for support of steam infusion mashes)
- (32) Pump and Valve On/Off outputs (Using up to 4 optional MUX boards providing 8 outputs each)
- (8) Temperature sensors (HLT, Mash, Kettle, CFC H2O IN, CFC H2O Out, CFC Beer Out, AUX1 and AUX2)
- (3) Optional Volume sensors (pressure transducers) used to measure HLT, Mash and Kettle volume (currently being tested)
- (1) Optional Steam Pressure sensor for controlling steam heat
- Simple encoder input providing iPod like controls (rotate left, rotate right, click for enter, click and hold for cancel)
- 20 column, 4 row backlit LCD character display
In closing the “controller section” I recommend the LOVE control for easy use and visiability and the BCS-460 for a more advanced user who wants more control.
Electricity: Based on how you brew, you may need 12, 24, 120, or 240 volts depending. If you are using an electrical heating element, you may need a 240 volt power source. These are considerations you need to make prior to ordering your temperature control. The Love and Ranco both offer different voltage options and function as their own relay.
The BCS-460 and Brewtroller use relays. A relay can be thought of as an automatic wall switch. You flip the switch up to turn the light on, you flip the switch down to turn it off. The only different is, the relay does the “flipping” by way of a low voltage input. An example would be the BCS-460. My BCS-460 sends a 5volt signal to the relay by way of CAT5 network cable. The other side of the relay circuit can be 24v, 120v, or 230v. I use 24v on my system to control two seperate Honeywell Gas Valves. When the 5volts flows to the switch, the circuit is closed allowing the gas valve to be turned on. With the BCS-460 and BrewTroller, every output needs to have a relay. (Again, an output could be your heater element, gas valve, or pump)
Gas Valve – I am using the term “gas valve” loosely because the ASCO I will discuss is not really a gas valve, it is a solenoid. There seems to be numerous options available for controlling the flow of gas to the burner.
Those who have built a Brutus Ten are most likely familiar with the ASCO Valve. Think of the ASCO valve as a switch which sits in the middle of a gas pipe. There are different voltage options available to use with the Asco Valve and they can be wired with a relay. I started out with ASCO valves but quickly changed them out after safety concerns. Using the ASCO method, I created my own pilot burner (flame near the burner). The pilot burner is supposed to stay lit during the entire brew process so when gas is allowed to pass throught he ASCO valve to the burner, it ignites. The pilot burner is completely independant of the ASCO valve. What this means is gas flows through your burner when heat is called for regardless of the pilot being lit or not. This means that if the pilot burner blows out, gas can flow through your burner without being ignited creating a safety hazard.
I prefer a standing pilot gas valve. In fact, I own two of the Honeywell Standing Pilot Gas Valves. One for my Hot Liquor Tank and One for my Mash Tun. This system consists of a standing pilot gas valve, a thermocouple, and pilot burner. It is very similar to the gas valves used in hot water heaters. This system has safety built into it. The thermocouple senses heat from the pilot burner. If the pilot burner is not “burning”, the thermocouple does not sense any heat and doesn’t allow gas to flow out the gas valve. I consider this a much safer system than the ASCO system.
Temperature Probe - Each controller recommends its own temperature probe style. Depending on the style of probe, you may need to purchase a thermowell. A thermowell can be thought of as a stainless (or copper) sleeve which fits inside the mash tun.An important issue witha Beer Brewing Temperature Control is the placement of the probe. I recirculate my mash during the entire 60 or 90 minute mash. My temperature probe is place on the return to the top of my mash tune. I have written a related article regarding temperature probe placement and it can be found here. http://www.gbrewing.com/2009/11/09/mash-tun-temperature-probe-placement/ .
I hope you are able to using some of this information as considerations when building your new beer brewing temperature control system.
(Disclaimer – I am not training you in how to wire or assemble any products. I am not teaching you how to become a pipe fitter or plumber. I am simple stating my opinion. Assemble any of these components at your own risk. Propane and natural gas can be dangerous and can cause serious injury and/or death. Electricity is dangerous and can cause electrocution hazard which can lead to serious injury and/or death – Always consult a qualified professional)