HLT & MT Automation

[Dave Parry]

Just thought I’d update you on a little project I’m working on.

The objective is to automate the heating of the strike water and the mashing so that the first 2+ hrs of brew day can happen while I am sleeping or at work.

Note I have built a simple HERMS system (coiled 10mm copper pipe from Mash Tun output in to the HLT and back to MT) that make this possible and I’m in to electronics.

The process goes like this:

1. Fill HLT and Mash Tun (12.5 l) with cold water the night before.
2. Put the grain bill in the cold water in the mash tun just before going to bed, and stir. Start the electronics box running (details below) and put the HLT heater on a timer to come on 2hrs before you get up.
3. The timer comes on and starts heating the HLT.
4. As soon as it reaches 65 deg C, the electronics box starts the HERMS pump which circulates the Mash water through the heat exchanger in the HLT and heats it up to 65.
5. As soon as the Mash Tun reaches 65, the pump turns off (and maintains 65 by turning off and on as required).
6. 10 mins before mashing time, the target temperature increases to the mash out target (typ 75).
7. Wake up (or come home from work) and start sparging.

I know there are concerns about the grist being in cold water for 4-6 hours before it starts heating up but I’ve had no problem so far and you can think of it like an acid rest followed by a protein rest.

The electronics box is a lcd display powered by an Arduino controller, two thermo couple sensors and an output to turn the 12v pump on and off.

Just sharing, but happy to get any suggestions on potential problems people can foresee or potential extensions to the functionality I could build in.

Photos below:

https://photos.app.goo.gl/iDUEBWVyCzQcAmDy5