So, an overview of the project I'm working on is that I am basically trying to make a temperature and humidity controlled environment in a plastic tote. Currently, the plan is to control it all via a Libre Computer le Potato. The computer will communicate with a relay which will turn the heat, cool, and humidifier on and off. At this point the project is close to done, however I am struggling to come up with something to use as the cooler. It only needs to cool a small space (average size plastic tote you see at Walmart or Target), so I do not need anything big. From other forums I found that Thermoelectric Peltier coolers might be the right option for my application, but I am not sure which ones are good and which are not. I also am open to suggestions on heating and humidifying, currently my plan is to just purchase a small heater and a reptile humidifier from amazon.
Any suggestions or modifications to the plan are welcome, I would love some feedback. If you know of any good and affordable ($40-$60) coolers, heaters, or humidifiers that would be awesome.

 

Welcome to AAC!
Search for TEC1-12706. They are inexpensive and readily available.

 

You can find them everywhere. I have no idea if some are better than others. What's more challenging is finding good technical data. I like the suppliers that actually provide such information.

There are a couple more but here's one example.:
https://www.analogtechnologies.com/tec-module.html

 

The described assembly will require a minimum of two relays, more likely three of them, one for humidity increase, one for heat, and one for cool. And the power for Peltier cooling is usually a few amps. And the cooler module should have a heatsink and a fan.

 

The described assembly will require a minimum of two relays, more likely three of them, one for humidity increase, one for heat, and one for cool. And the power for Peltier cooling is usually a few amps. And the cooler module should have a heatsink and a fan.

I will be using a 4 relay module for this project

 

First, You should decide what means word "good".
Good at gaining the ultimate high dT?
Good to have ultimate high power?
Good with the best efficiency factor?
And those three never be in one element, as they are contradicting one to each another.

Then, must decide HOW TO cool the hot side. Most of the Peltiers have enormous high power density to microscopic area. Thus, the normal air natural or fan driven coolers are many orders of magnitude inappropriate. They customarily are driven by water cooler. However theoretically is possible to apply the Heatpipe coolers from PC bold end videochart.

 

You can buy a cooler complete with Peltier built-in, and with heat-sinks and fans to circulate and cool. I've paid less than $1 at yard sales.