DIY Fermentor - Advice before i start

[mcscruff]

Hi all.

Im going to build myself a fermentor. I looked around at other builds and using a fridge seems the best way for me. I see everyone uses systems like the inkbird but I want mine to do a little more.
Can anyone see an issue with using a fridge, a greenhouse heater (heat tube) hooked up to a power relay ( Like This)
Then also using the pi with a temperature probe.
I would write a python script to take a reading every x mins, then turn on/off the heater/fridge.

The plus side of this would be it on wifi and being able to monitor it wherever i am, alert me if something goes wrong etc.

 

[Jim Brewster]

I haven't moved onto temp control yet, I think people use an Inkbird because it's a proven off the shelf solution.

I'm sure you could build the same sort of thing from parts, with sensors for current temp, a set target temp and a tolerance temp so the refrigerant compressor or heater isn't turning on and off every few seconds

 

[chthon]

One thing I noticed with these setups is that sooner or later an error occurs with the temperature probe, and then the system starts to heat continuously.

In this case, since you would write the script yourself, I think you should check if you can check the status of the probe, e.g. if a signal is delivered or not, and turn off everything and set an alarm if you don't get a correct signal. The same with maximum temperature. If your probe e.g. registers above 30° C, turn off the system and set an alarm. I suppose I could find a couple more error states, not only based upon temperature, but also based upon duration of too low or too high temperatures.

 

[mcscruff]

One thing I noticed with these setups is that sooner or later an error occurs with the temperature probe, and then the system starts to heat continuously.

In this case, since you would write the script yourself, I think you should check if you can check the status of the probe, e.g. if a signal is delivered or not, and turn off everything and set an alarm if you don't get a correct signal. The same with maximum temperature. If your probe e.g. registers above 30° C, turn off the system and set an alarm. I suppose I could find a couple more error states, not only based upon temperature, but also based upon duration of too low or too high temperatures.

With me writing the script, i would add failsafes, if the probe fails to get a reading after 3 attempts then shutdown and send a push notification to my phone, if it reads above or below x then turn off everything and send a push notification.
It also lets me ssh into the pi and do other checks. Another i would have is a manual thermostat and use the camera module to view it remotely

 

[GeorgieV]

Hi all.

Im going to build myself a fermentor. I looked around at other builds and using a fridge seems the best way for me. I see everyone uses systems like the inkbird but I want mine to do a little more.
Can anyone see an issue with using a fridge, a greenhouse heater (heat tube) hooked up to a power relay ( Like This)
Then also using the pi with a temperature probe.
I would write a python script to take a reading every x mins, then turn on/off the heater/fridge.

The plus side of this would be it on wifi and being able to monitor it wherever i am, alert me if something goes wrong etc.

This is pretty much what I do. The only difference is I use iSpindel for a temperature probe and a heating mat with wifi socket. Works perfectly well. This is my setup for fermentation temperatures above the expected ambient.

 

[jof]

It's not complex, you could save your pi & use a cheaper Arduino clone to do a job like that.

Alternatively there are pre built modules for temperature control.

Something like stc-1000 for around £10

 

[Agentgonzo]

Depending on how adventurous you are feeling, you could swap out the python script for a homeassistant installation. If you can get the inkbird/probes connected to it, then it'll save you writing the custom logic and UI for it (I have one with a variety of simple automations/sensors based around it for the house). Once it's installed and hooked up, it's far simpler setting up automation rules with their UI/builder than manually writing python scripts.

 

[Branny]

The 308 wifi has a whole host of 'smart' features and automations which inc event, notification and event response. I do my stuff manually so never used them. That said, I completely get the notion of doing the genius stuff yourself!

 

[keith thomas]

Hi all.

Im going to build myself a fermentor. I looked around at other builds and using a fridge seems the best way for me. I see everyone uses systems like the inkbird but I want mine to do a little more.
Can anyone see an issue with using a fridge, a greenhouse heater (heat tube) hooked up to a power relay ( Like This)
Then also using the pi with a temperature probe.
I would write a python script to take a reading every x mins, then turn on/off the heater/fridge.

The plus side of this would be it on wifi and being able to monitor it wherever i am, alert me if something goes wrong etc.

You might consider a solution which a mate and I thought up after a few pints. We built a box out of 50 mm Kingspan big enough for 2 fvs and taped some soil warming cable to the inside. We reinforced it with 1/2 inch dowel. It's controlled by a thermostat and mounted on a piece of plywood fitted with casters so I can move it around the workshop. Just be careful to get a controller that has the right temperature range because some of them are designed only for frost protection and don't go high enough. I can send pics if you're interested.
Cheers. Keith

 

[mcscruff]

You might consider a solution which a mate and I thought up after a few pints. We built a box out of 50 mm Kingspan big enough for 2 fvs and taped some soil warming cable to the inside. We reinforced it with 1/2 inch dowel. It's controlled by a thermostat and mounted on a piece of plywood fitted with casters so I can move it around the workshop. Just be careful to get a controller that has the right temperature range because some of them are designed only for frost protection and don't go high enough. I can send pics if you're interested.
Cheers. Keith

I would love to see a few pics.

 

[keith thomas]

I would love to see a few pics.

Hope these give you the idea. Dimensions are 890x535x700high. With a bit of care you can get the whole box out of one sheet. We put duct tape around the top edges to stop them crumbling and I recently added a solid top so it can be used as a work surface when bottling. The thermostat can be set pretty precisely and works really well. Let me know if you need any more details.
Cheers. Keith

 

[tigertim]

That looks really great! I’ve been planning something similar but for dispense instead of fermentation.

I already have a shelf cooler which supplies chilled water to my fermenters, so plan to build an insulated enclosure for my kegs which is cooled using the kinds of fans and radiators used for water cooling by PC overclocking enthusiasts.

The only downside is that these kinds of radiators are intended for use on the hot side rather than the cold side, so they are not designed with condensation management in mind (I.e. drip trays). So that would have to feature as part of my design. I’m up for the challenge though

 

[keith thomas]

That looks really great! I’ve been planning something similar but for dispense instead of fermentation.

I already have a shelf cooler which supplies chilled water to my fermenters, so plan to build an insulated enclosure for my kegs which is cooled using the kinds of fans and radiators used for water cooling by PC overclocking enthusiasts.

The only downside is that these kinds of radiators are intended for use on the hot side rather than the cold side, so they are not designed with condensation management in mind (I.e. drip trays). So that would have to feature as part of my design. I’m up for the challenge though

Yes I've noticed on the controller that there are two settings. One for warming and one for cooling so you could use it with fans.
Good luck!

 

[mcscruff]

Hope these give you the idea. Dimensions are 890x535x700high. With a bit of care you can get the whole box out of one sheet. We put duct tape around the top edges to stop them crumbling and I recently added a solid top so it can be used as a work surface when bottling. The thermostat can be set pretty precisely and works really well. Let me know if you need any more details.
Cheers. Keith

Great build.
What do you do for cooling if it gets too warm?.

 

[keith thomas]

Great build.
What do you do for cooling if it gets too warm?.

Good question! I live in Scotland so cooling doesn't seem to be a problem! To be fair our initial issues were all to do with keeping the brews warm enough to keep going in an unheated workshop and heating was the issue. I don't check the temp in the workshop but I'm sure it never goes above 20 C.
I'm sure elsewhere you have different problems.
Cheers. Keith

 

[peebee]

... I think people use an Inkbird because it's a proven off the shelf solution. ...

If you're talking about the ITC-308, it's proven to be a defective solution!

Well, I wasn't going to let that bit of mis-information stand was I.

https://www.thehomebrewforum.co.uk/threads/issue-with-inkbird-itc308s-anyone-else-had-this.81916

 

[mcscruff]

Thank you to everyone,

My build has started.

Got an Inkbird 308 and a tube heater cheap on fb, so i went with those. I will at some point finish lining the rest of the inside. And i need to add some cooling, i think this will just be a couple of pc fans, and if that isnt enough (during summer) i can always put a bucket of ice below a fan intake. (I am also looking into pc water cooling).

Im no DIY expert, but i think this will do for now

 

[Guzzie]

I am looking to build a similar box so will be interested in seeing your final build.
For a cooling element - I have thought about using the top electronics from a coolbox connected to an Inkbird. I see Aldi and Lidl have them on sale this week. G

 

[Chippy_Tea]

And i need to add some cooling, i think this will just be a couple of pc fans, and if that isnt enough (during summer) i can always put a bucket of ice below a fan intake. (I am also looking into pc water cooling).

Instead of making a box that you are then going to have to cool in some way later why not start with a second hand fridge and an inkbird controller?

 

[mcscruff]

Instead of making a box that you are then going to have to cool in some way later why not start with a second hand fridge and an inkbird controller?


View attachment 70743

I did have that idea too, But 1 of my fermeters i am currently using does not fit in my Fridge (height) so i decided to build one that i can put at least 2 of them in