Smart Keezer Build (IoT - Pi - ESP8266/ESP32)

[TheSkaz]

Creating a thread to document my specific build.

Actual build:
https://www.homebrewtalk.com/showthread.php?t=631219

RPints will be installed:
https://www.homebrewtalk.com/showthread.php?t=487694

A version of the Temp display will be added on:
https://www.homebrewtalk.com/showthread.php?t=469523

The goal is to have the tap list and temp sensors displayed on a screen. I currently dont have an interest for graphing or archival data. Maybe later. My goal is to have a Pi that is completely decoupled from the keezer, and not required for basic keezer functionality.

I currently have a NodeMCU 1.0 ESP8266 hooked up to the keezer. I also have an adafruit Huzzah and a couple of ESP32s. I am going to try to get this to work on the ESP8266 and if I cant, move over to the ESP32. I will have 2 temperature sensors (OneWire), 2 Relays (one for fans and one for Compressor) and 6 adafruit flow meters. At the moment I have a little OLED 0.96" screen mainly to help troubleshoot while I work on this. I ultimately would like to build a PCB that can make all this way simpler. Hopefully with connectors for the flow meters and temp sensors.

I am breaking this out because it was/is pretty tough to parse through 300 or so total pages of posts. And if anyone wants to do what I did, there is a concise location.

So first task to to get the ESP to send data to the pi. all 6 pulses and 2 temp readings.

 

[TheSkaz]

I planned on having more to say at this point, but it took me 4 days to just find the adapters for the adafruit flow meters. The ones that people use from grainger are discontinued. I finally found some here:

https://www.qcsupply.com/female-thread-x-hose-barb-nylon-fitting-1-2-fpt.html

just ordered them a few minutes ago. Hopefully this will help someone who is looking for the adapters for the adafruit flow meters here: https://www.adafruit.com/product/828

 

[TheSkaz]

Update:

Got the adapters, and noticed NPS on the meter threads, and NPT on the adapter... so... gotta figure that one out, maybe an oring or something. I have plenty of teflon tape on it.

on a better note, I extended the wires to the ESP8266 and ready to flash the new sketch as soon as stuff stops leaking.

 

[TheSkaz]

Update yet again:

Upgraded to the ESP32 as I have a few of them around and did not have enough GPIOs for 6 taps. I think it's overkill, but i dont have a GPIO expander to use with my esp8266.

I'll upload my ino file here: https://github.com/hicotton02/KeezerController

At this point, the relays work with the fans and such, but the pulses dont.

 

[TheSkaz]

So I finally got a schematic done for the board using an ESP-12 and MCP23017. It took so long because this is my first foray into this level of development. usually i just end with a breadboard and jumper wires. This time I plan on making a board. before I get into it, I know there are some engineers lurking around and would like to see if this schematic makes sense. I have a couple concerns around capacitance type and size, diode type, and general layout/design.

This is designed to take 12v in. power the fans, then convert it to 5v for the relay and the flow meters, then bring it down to 3.3v for the ESP, logic, etc.

 

[atariplayr]

Hi. What was your final solution for the adapters for the flow meters?
I'm also having difficulty finding them with NPS thread...

 

[TheSkaz]

I used the ones above with thread tape AND an O ring. I cant recall where i got the O rings. they are the thick ones.

I am still developing on this actively and waiting for components to come in the mail.

 

[atariplayr]

Good luck! I just finished my RaspberrPints install for a 2-tap system. I just need to get adapters for the flow meters to get it all installed and then calibrate the flow meters....