Hi all,
The CoolBot is a great innovation, but too expensive ($350).
If cost is not an issue, go for it, but here is a much cheaper solution you may want to consider:
Since most AC unit temperature sensors are thermistors you can simply change the value and fool the controller so that the temperature range is shifted downwards.
I did this for a portable room AC unit I'm currently using in my wine cellar.
The thermister is a 10K and I connected a 100K resister in parallel.
This trick brought down the minimum temperature setting from 62F to around 53F,
This works for me.
All I do is remove the sensor from the coil and re-position it to the outside of the unit. Pretty much does the same thing.