Frequently Asked Questions
°CoolBot Questions
Yes! We have a ton of independent data to suggest that using a °CoolBot with a properly sized (based on our sizing tables) window air conditioner or a ductless mini-split air conditioner is more efficient than a conventional refrigerator compressor.
We’ve had hundreds of customers give us feedback about their lower electricity bills versus the conventional refrigerator compressor they used to have.
Additionally, NYSERDA, (the NY State Energy Research and Development Authority) contracted for an independent analysis to measure the efficiency of a °CoolBot-driven system versus a standard cooler.
This Report from NYSERDA (New York State Energy Research and Development Authority) confirms that the °CoolBot works great and does not stress out the air conditioner or push it into unacceptable cycle times (which is another question that we get asked a lot). NYSERDA found that under certain conditions a °CoolBot-driven system can be up to 40% more efficient than a conventional refrigerator.
Although the °CoolBot-driven system is typically over-sized versus a conventional cooler from a BTU perspective, it saves so much energy as an air conditioner typically uses only one 300 watt fan, while a conventional refrigerator compressor uses 3, 4 or 5 fans, depending on the size. One major benefit to a one-fan system is that certain flowers and crops (e.g. delicate flowers or baby lettuce) will stay fresher for longer due to the reduced air movement in the cooler. The trade-off is that our recovery times back to the desired temperature can be slower than a conventional compressor if the door is left open and the cool air is allowed to escape.
The °CoolBot is not just a thermostat! The °CoolBot is a device which uses multiple sensors and a programmed micro-controller, which when attached to a standard off-the-shelf air conditioner, functionally replicates a more expensive conventional walk-in cooling system.
The °CoolBot does include a digital thermostat so you can set it to run at whatever temperature you want between 32°F – 65°F ( 0°C – 18°C ). However, the minimum recommended temperature is 34°F to avoid freezing up the A/C.
Sure! There are a few options:
- Recommended- Buy an extender from any electronics store; just be sure the plug fits exactly (2.5mm mono extender cable)
- You can splice in a little more “stranded wire” using very light gauge wire and wire nuts. 24 gauge wire is probably fine for just 3 feet, or you can use a heavier gauge wire for longer extensions.*
*It will void the warranty on the sensor cable that you cut, but it won't void the warranty on the °CoolBot. If the splice doesn’t work, head to our Shop to purchase a new cable.
We designed the °CoolBot to work in a cool, dark and moist environment. Prolonged exposure to the sun can impair the °CoolBot’s buttons, and mounting the °CoolBot’s wires through the wall could damage them.
If you want to know the temperature of the cooler from the outside we strongly suggest either an economic indoor-outdoor thermometer mounted outside, or if you have WiFi, upgrading to the °CoolBot Pro to monitor your cooler and get notifications via the WiFi module.
Yes! We have customers using solar power to run their systems. The systems can be expensive due to the inverters and batteries.
Another option is to use a back-up generator for situations where the grid is unreliable.
For folks who are using solar power, the keys to success are using a mini-split A/C (for energy efficiency) and keeping the cooler as small and well insulated as possible.
We have limited experience with solar applications but we’re happy to help with any information for any one who wants to do it.
When we first started the Company in 2006, we were really active about connecting people. Since then, we have over 60,000 installations in every state, so there is a chance that someone near you is using a °CoolBot right now. Unfortunately, we don’t share customers’ names and businesses information anymore for privacy and management reasons. However, we do have a ton of customer testimonials and blogs sharing their stories.
You can see testimonials for your specific use case on the following pages:
We also have links to online and print articles about the °CoolBot on our Press page.
Finally, we’re actively recommended by multiple land grant colleges (such as UC Davis, Cornell Small Farms Program, and University of Vermont) and the USAID program in coolers large and small. In fact, quite a few universities as well as NASA’s SATOP program have contributed plans and support to °CoolBot, including some financial cost-share programs for small farmers who want to buy °CoolBots to save money. See our Research page for more information.
Unfortunately, there aren’t any NSF certified air conditioners, so no restaurant with an air conditioner in their commercial kitchen will have them NSF certified.
The °CoolBot system is running in many inspected commercial kitchens as well as in many inspected meat processing operations with no problem. Many people have also build their own coolers and use FRP (fiberglass reinforced panels) on the inside. These panels are NSF certified to use as finishing surfaces for their walk-in cooler panels. Before deciding to build your own walk-in Cooler or to use a °CoolBot system for your commercial establishment, we recommend to always check with your local Inspectors to find out what is necessary to comply with codes in your area.
The CoolBot controller is legally classified as a thermostat or Temperature Regulator, and there are no NSF certified thermostats. There are NSF thermometers which is different. °CoolBot has a UL listing that classifies the °CoolBot as a safe device to use in combination with an A/C unit to allow it to regulate the temperature of a space.
Our newest °CoolBot Pro can keep a log of temperatures and give alerts to their users via text when temperatures go outside of a set range. This has proven very useful for places that need constant and critical monitoring and a good tool for inspectors. The log can be accessed via the free °CoolBot Pro web based app from any device at any time and can be shared with as many users as you want.
The best thing to do is ask your local inspector ahead of time about using the CoolBot in your business. We have 60,000+ units out in the field, thousands of which are in commercial kitchens. We would be happy to speak with a local inspector who is concerned or have questions regarding the °CoolBot. Ultimately, it is their decision to allow you to use a °CoolBot system in your business.
Air Conditioner Questions
We have a sizing and brand recommendation chart available on our How To Choose The Right A/C section. That section has general sizing guidelines that will work for most users.
Since sizing of a refrigeration system depends on a lot of factors including cooler insulation, ambient temperatures, ground temperature where you live, product being stored, if the cooler is indoors or out in the sunshine, etc., you are welcome to reach out to us via our Cooler Construction Advice Form and we will get back to you with the best recommendation for sizing an A/C for your cooler.
Surprisingly it will not!
A °CoolBot-driven A/C in a walk-in cooler will cycle less than it will in a residential setting.
In your tightly insulated walk-in cooler, the A/C compressor will cycle on far less than a residential setting. Most of our customers with well-insulated cold rooms and properly sized A/Cs, report that the A/C compressor runs in average 30% – 50% of the time compared to 75% – 90% in a residential setting during hot summers.
We do not recommend using the Energy Saver mode. If you do, there are pros and cons to consider:
Pros of running Energy Saver Mode:
- Saves a little more on electricity
- The fan turns off when the compressor turns off, but the fan will still periodically cycle on to circulate air in the room
Cons of running Energy Saver Mode:
- The room recovers from door openings more slowly
- If the fins freeze up, it is probably too warm outside to run in Energy Saver, so you would need to switch back to the Cool mode
- It cools down field-hot produce more slowly (especially for higher quantities of produce). if you load up a lot of produce, you should switch out of Energy Saver and reset your heater settings back to “d1”
If you do decide to run the AC in Energy Saver, we recommend to change the HEATER Delay setting up to “d3” from the default of “d1”.
To do that, do the following:
- Tap the RIGHT arrow to go into “Heater” mode (the light under “Heater” will be on, and “F” will be in the display if you are in the US, “C” if you are elsewhere)
- Tap the CHECK MARK button 3 times (or until you see “d1” blinking in the display)
- Tap the right arrow twice to change to “d3”
- Press the Check mark once to save the new setting. The display reverts back to normal (displaying room temperature) in 20 seconds
Some A/C’s display the air conditioner's set temperature all the time, in most cases it will be 60F.
Other A/C’s display the temperature that the A/C’s temperature sensor (the one connected to the CoolBot’s heater) is reading. When the CoolBot heater is on, it is calling for the A/C compressor to come on; therefore on these type of A/Cs, the A/C may display a high temperature of 80°F+ (32.2°C+). This number will drop rapidly when the °CoolBot cycles off.
Regardless of what the A/C digital display says, the °CoolBot will display the actual room temperature. It has a very sensitive temperature sensor, and will change quickly with air movement. If you need to see temperature from the outside of the cooler, a lot of customers install an indoor-outdoor thermometer or if you have WiFi available near your cooler, you can now monitor and get notifications with the new °CoolBot Pro and a WiFi module.
Yes! The temperature will drop down faster, recover from door openings quicker, and be able to get colder than 36F. Keep in mind that the A/C will cycle on for shorter time and this will most likely increase the relative humidity on your room.
For example, our recommendation for an 8x8x8 room is 12,000 BTU’s to be at 38°F or above. If you bumped up one or two sizes you’d be at 15,000 BTU’s or 18,000 BTU’s. In both cases, you get more surface area to transfer cold, so you could run in Energy Saver mode most of the time (it’s best to run in standard mode an hour before and after loading up and if it’s extremely hot outside) or run on the recommended Cool mode but have faster recovery times or colder temperatures than 37°F.
Also, 18,000 BTU and 24,000 BTU air conditioners both run on 220 volts. That means you have less amps running on each leg of your power cord and your compressor will run more smoothly.
CAUTION! If you are over-sizing the A/C for your room from the sizing recommendation we have for that room size, DO NOT use a Frigidaire, Arctic King, Danby, Kelvinator, Noma or Perfect Aire. You will experience colder than set temperatures and may experience icing problems.
Yes! We have customers successfully using multi-zone mini split systems with the °CoolBot. Make sure it is a Mini -Split of a compatible brand. Check our How To Choose The Right A/C. page for more information.
You need to be sure the outdoor unit of the Mini-Split is able to accommodate the BTU needs for all zones. For example, if your walk-in cooler needed an 18,000 BTU unit, and there were 3 other units that handled 8,000 BTU each, then you would need an outdoor unit (condensing unit) that was able to handle 42,000 BTUs. Each zone operates independently from the others, so you can maintain different temperatures in each zone.
Don’t bother getting an A/C with the highest SEER or EER. Try to focus in getting a compatible brand instead.
Inverter or non-inverter? The °CoolBot does not know the difference and will still work the same as long as it is a compatible brand of A/C.
Uses Questions
Yes! We have thousands of hunters and many small commercial meat processing facilities using °CoolBots to keep their meat cool.
For more information on coolers for hunters and meat processors, check out our page: Hunting & Meat.
Yes! Thousands of florists use the °CoolBot to keep their flowers cool, and we’re recommended by the American Society of Cut Flower Growers. See our Floral page for more information and best practices!
Yes! The °CoolBot is a great option for people wanting to keep their wine cellar cool.
50°F – 60°F (10°-15.6°C) is no problem for the °CoolBot. With consistent temperature and humidity between about 50% – 80%, we can keep your wine in the perfect conditions.
See the Wine Cellar page for more information and best practices!
Many more! The °CoolBot is found in many applications we didn't even thought of - from live crabs, to bees, to bakeries, to mortuaries, to seed storage, to curling stones and many more we have been there.
Not sure if it will work for you? Just contact us and we will be happy to help!
Unfortunately, there aren’t any NSF certified air conditioners, so no restaurant with an air conditioner in their commercial kitchen will have them NSF certified.
The °CoolBot system is running in many inspected commercial kitchens as well as in many inspected meat processing operations with no problem. Many people have also build their own coolers and use FRP (fiberglass reinforced panels) on the inside. These panels are NSF certified to use as finishing surfaces for their walk-in cooler panels. Before deciding to build your own walk-in Cooler or to use a °CoolBot system for your commercial establishment, we recommend to always check with your local Inspectors to find out what is necessary to comply with codes in your area.
The CoolBot controller is legally classified as a thermostat or Temperature Regulator, and there are no NSF certified thermostats. There are NSF thermometers which is different. °CoolBot has a UL listing that classifies the °CoolBot as a safe device to use in combination with an A/C unit to allow it to regulate the temperature of a space.
Our newest °CoolBot Pro can keep a log of temperatures and give alerts to their users via text when temperatures go outside of a set range. This has proven very useful for places that need constant and critical monitoring and a good tool for inspectors. The log can be accessed via the free °CoolBot Pro web based app from any device at any time and can be shared with as many users as you want.
The best thing to do is ask your local inspector ahead of time about using the CoolBot in your business. We have 60,000+ units out in the field, thousands of which are in commercial kitchens. We would be happy to speak with a local inspector who is concerned or have questions regarding the °CoolBot. Ultimately, it is their decision to allow you to use a °CoolBot system in your business.
Humidity Questions
Yes! The °CoolBot / Air Conditioner combination has no trouble running in high humidity conditions – inside or outside the cooler.
We have customers in the bayous of Louisiana, the jungles of South America, India, equatorial Africa and even down in Papua New Guinea, all running with no problem in near 100% humidity outside their coolers.
To achieve extra dehumidification, there are a few options:
- Keep the room sealed tight: Make sure all gaps and cracks in the cooler are caulked or spray foamed to prevent warm air from entering the cooler. Make sure the gasket around the door keeps a tight seal, and replace the gasket if it is cracked. Warm air carries a lot of moisture that raises the humidity level in the room once it cools down, and even small cracks are constantly bringing in a flood of moisture.
- Minimize door openings: Adding PVC door flaps (curtains) to the entrance of any cooler is a great way to reduce warm air entry.
- Try different temperature settings: You may find that storing at 42°F (5.6°C) gives you a steady-state of 50% relative humidity; but, if you drop the temperature down to 35°F (1.7°C), you end up with a relative humidity of 70% . Try different temperatures and see where you end up.
- Use a mechanical dehumidifier: It needs to be one that says it works in basements. Be sure your air conditioner is large enough to compensate for extra heat produced by the motor in the dehumidifier. Here is an example of a low-temp dehumidifier.
- Use chemical desiccants:
- Calcium Chloride. This has been the solution for a few people in developing countries where electricity is unreliable. While the quantity of CaCl2 affects the amount of humidity that is removed, the CaCl2 is able to remove twice its weight in moisture and can bring rooms down to 30% relative humidity. We have also heard that it can be dried and re-used.
- We find that Sodium Chloride doesn’t work well. Its steady state keeps a relative humidity of 72% at best, so it’s not great for seed storage.
For whichever method you choose, be sure to leave space around the product for adequate air circulation!
The humidity level with a °CoolBot and air conditioner usually ends up in the 70% – 90% range. If the cooler is empty or nearly empty, it will be slightly drier than if it is more full.
Even in a dry climate like Arizona, coolers usually end up in that 70% – 90% humidity level. Outside it might be 25% relative humidity, but when you open the door and that hot/dry air comes rushing into the room, it very quickly cools down to 50°F – 60°F (10°-15.6°C) degrees. Therefore, that exact same air that outside measured at a relative humidity of 25% will now measure at a relative humidity of 70% – 90% inside the cooler. Colder air can hold much less moisture, so the humidity levels go way up. Physics is great!
If you need more humidity, you’ll have to use a humidifier, and there is no conflict with running a humidifier and a °CoolBot. Simple and cheap vapor humidifiers can even come with humidistats to measure ambient humidity. Other options to increase humidity are adding buckets of water (flowers) or running the A/C on Energy Saver mode (see °CoolBot FAQ about running A/C on Energy Saver).
If you need lower humidity, you’ll have to use a dehumidifier – which means you’ll have to account for the extra heat that the dehumidifier puts out (which just means up-sizing the air conditioner a little). It is worth also checking the basics of your cooler: Is insulation adequate? rigid foam or spray foam? is it airtight? are the gaskets around the A/C and the door gaskets in good condition? Is the A/C grossly over-sized for the room? Installing vinyl walk-in cooler plastic curtains at the entrance helps tremendously decrease air exchanges due to door openings and keeps recovery times lower.
Yes, it will definitely work with higher humidity.
Florists, flower growers, and cheese-makers who want higher humidity in their coolers seem especially happy with the °CoolBot. A °CoolBot-driven A/C moves much less air than a standard refrigerator compressor, and flowers dry out less and last longer. We have some additional humidity tips on our Dairy and Floral use-case pages as well.
You can also pick up a commercial humidifier to add to your cooler setup.
Yes! The °CoolBot maintains the perfect relative humidity for vegetables and fruits. There is a misconception that air conditioners constantly dry out the air, but most coolers reach a steady state humidity range of 70% – 90%.
If you want higher humidity levels, you can add humidifier with a humidistat into the cooler. It will not affect the function of the °CoolBot or air conditioner. Other options to increase humidity are adding buckets of water (flowers) or running the A/C on Energy Saver mode (see °CoolBot FAQ about running A/C on Energy Saver).
For food safety and to minimize disease pressure in your produce, we think it’s better to think about humidity control on a “micro-climate” level. We recommend that you use proper storage containers: for example, use mostly closed crates for things that need higher humidity (baby lettuce) and more open crates for things that need lower humidity. For berries, use clamshell boxes.
You don’t have to spend a lot of money to store your produce for the optimal humidity levels: On the Huguenot Street Farm, Ron and Kate mostly used open sided/open topped crates, but then used plastic to line crates or lay over the top of open topped crates, and that worked fine.
Yes, but you might need extra dehumidification. The °CoolBot is used in many seed storage facilities all over the world, and they all want to keep the combined humidity and temperature in Fahrenheit under a total value of “100”.
To achieve this, there are a few options:
- Try different temperature settings: You may find that storing at 42°F (5.6°C) gives you a steady-state of 50% relative humidity, so that’s a total of “92”; but, if you drop the temperature down to 35°F (1.7°C), you end up with a relative humidity of 70% (putting you at “105”). Try different temperatures and see where you end up. Our experience has been the right number for most people who don’t want to use any external dehumidification controls is going to be somewhere between 40°F – 50°F (4.4°-10°C).
- Keep the room sealed tight: Make sure all gaps and cracks in the cooler are caulked or spray foamed to prevent warm air from entering the cooler. Make sure the gasket around the door keeps a tight seal, and replace the gasket if it is cracked. Warm air carries a lot of moisture that raises the humidity level in the room once it cools down, and even small cracks are constantly bringing in a flood of moisture.
- Minimize door openings: If you have a commercial seed storage facility with a lot of traffic, add PVC door flaps to reduce warm air entry.
- Use a mechanical dehumidifier: It needs to be one that says it works in basements. Be sure your air conditioner is large enough to compensate for extra heat produced by the motor in the dehumidifier.
- Use chemical desiccants:
- Calcium Chloride. This has been the solution for a few people in developing countries where electricity is unreliable. While the quantity of CaCl2 affects the amount of humidity that is removed, the CaCl2 is able to remove twice its weight in moisture and can bring rooms down to 30% relative humidity. We have also heard that it can be dried and re-used.
- We find that Sodium Chloride doesn’t work well. Its steady state keeps a relative humidity of 72% at best, so it’s not great for seed storage.
For whichever method you choose, be sure to leave space around the product for adequate air circulation!
Cooler Construction Questions
Unfortunately no, you can’t mount a window air conditioner in a sideways orientation on the ceiling.
The best setup for a cooler with no option to install a window A/C on the wall is a ductless mini-split air conditioner. The evaporator hangs on the wall in the cooler, the compressor sits on the ground outside, and the two are attached only by tubes and wires so you only need to make about a 3″ hole in your cooler.
Venting a window A/C into a non-climate controlled interior space such as a storage room or garage is fine. Venting the A/C into an air conditioned space is also OK, but keep in mind that you will be paying for the additional electricity to cool the warm air blowing into the air conditioned space.
Portable air conditioners are not a good option since they are unlikely to get your cooler below 54°F (10°C) even under the best of circumstances.
Yes! You can use most window air conditioners through a wall. One important consideration when mounting a Window A/C on a wall is to make sure that the vents on the back of the A/C enclosure (side and top) are not inside the wall. Sometimes, in order to clear the vents out of the wall, the A/C may have to be receded in the wall a few inches from the inside. If the vents of the A/C are inside the wall by a small fraction - that is OK, it will still work fine.
A/C's 12K BTUs are usually OK to be installed in walls that are ~8 inches thick or less.
A/Cs 15k BTUs and above are OK to be installed in walls up to ~11 inches.
If your wall is thicker and it cannot accommodate a window A/C (even if it is receded in the wall a few inches) consider these options:
- Ductless mini split air conditioner: The evaporator hangs on the wall in the cooler, the compressor goes on a concrete pad outside. They are connected by tubes and wires which run through a 3 inch hole.
- Through-the-wall air conditioner: Most manufacturers make a custom designed metal sleeve with all the necessary ventilation to use it in a thicker wall. Some are sold all in one piece, and some are an extra accessory for a standard window air conditioner. If you do decide to use a through-the-wall A/C, be sure to check out our Air Conditioner Sizing Guide to ensure the model will work with the °CoolBot.
Avoid putting a drain in your cooler if you can. For hunters and meat processors who regularly hose down the concrete floor of the cooler, you can install a drain, but be sure you have an air tight seal for it when you’re done using the hose.
A surprising amount of cold air will go out of the drain hole; you can warm up a cooler by 5 degrees Fahrenheit with just a 3 square inch drain!
For most users, a mop and bucket is the best way to clean the floor.
Cold air falls. By skipping the floor, you create an endlessly hungry “cold sink”. Concrete floors are a conductor (not an insulator) so no R value is gained there.
If you are pouring a concrete pad for your cooler, please use between R25 and R30 styrofoam underneath the concrete. You will have the benefit of the insulation and the easy maintenance of a concrete floor.
The only time you can skip a floor is if the ground temperature is less than 13°F warmer than the desired temperature in your cooler. (Do you live in Alaska? Are you only using the cooler for hunting when the ground temp is 53°F (11.7°C) or less? Do you only want the cooler to chill to 48°F (8.9°C)?) If you up size the air conditioner, you may be able to reach your desired temp, but it will cost you more in electricity and wear and tear on your air conditioner.
A truck or trailer will never cool properly without a well insulated floor. The cold air inside falls and heat from the road rises and warms the floor from the outside.
Produce farmers often ask this question for vegetables that like to be very cold and some more delicate vegetables that will get damaged at very cold temperatures.
It is possible to use 1 °CoolBot and 1 A/C to have two different temperature zones in a cooler, but we don’t recommend the setup. The main issues are twofold:
- Temperatures want to equalize so you won’t have much of a temperature difference between the two sides over some time (e.g. overnight)
- It is difficult to get the partition set up correctly. Plastic cooler flaps are not very efficient, and you can only expect a few degrees of temperature differential. It’s better to build a wall with a door and work at adjusting a crack under the door by about 1/4″ at a time to try to get the temperature you want in both sides of the cooler
Given the issues discussed above, we recommend 2 separate air conditioners and 2 °CoolBots for this type of setup. That way there is no guess-work around the partition set up and you can adjust the temperatures in the two coolers as needed.
Yes! You can build a cooler and vent your air conditioner into a basement, storage room or lightly used space. You would not want it to blow into an area where there are customers.
A few tips:
- Proper set backs are vital for the functionality of the air conditioner, at least 2 feet on each side, top and back of the A/C (check owners manual for exact set back requirements for your model!).
- Warm air will be vented into your basement from the back of the A/C unit. It’s just warm air, and it’s not harmful. If you have windows, you will want to open them a little, or install a vent or an exhaust fan to keep the space comfortable and the back of the A/C ventilated. If you live in a cold climate, this extra heat may be welcome in the wintertime.
- Water will drip from the back of the air conditioner, and normally you can catch it in a bucket, It’s usually just a small amount of water unless you live in a very humid climate or are opening the cooler door a lot, which will increase the amount of condensate.
Yes! 20′ x 20′ installations are common for us and may require the purchase of two, three or four air conditioners (each with a °CoolBot). The number of and size of the A/Cs depends on cooler height, temperature goal, ambient temperature, and volume of product coming in the cooler.
We have done larger installations, up to 60′ x 40′. Please call or email us with the details of your cooler and conditions to help determine your cooling requirements.
The easiest way would be to leave the drywall in place and add rigid foam insulation on top. Use at least 2 layers of Styrofoam insulation, stagger the seams, and be sure to seal the corners tight. Sheet rock and Batt insulation will mold if condensation forms on either of them. Use caulk and spray foam on every gap, crack, or seam to prevent air from leaking through.
The R value of the existing insulation counts when you’re building a cooler in a corner of an already insulated room. Add enough insulation to equal R25.
We highly recommend against building any sort of duct work around the system.
The area behind and on the sides of the air conditioner where the heat is exhausted needs to be free and clear of interference. Obstructions will cause the compressor to overheat and shut off. Check your owners manual, but a medium sized air conditioner will need at least 2 feet of ventilation around the back.
Ducting the cold air causes the fins of the air conditioner to freeze up. The fins will also freeze up if cold air is blowing toward the A/C from a fan. The cold air needs to be able to flow into the room freely.
Avoid boxing the A/C system in on either side for the best results.
Winter Season Questions
The air conditioners that have both heat and cool modes only heat at 60°F and above. They do not switch from cooling to heating automatically.
One solution that we’ve found is to buy a little heater (buy the blower type, not radiant type) like the Lasko Ceramic Heater or the Pelonis ceramic heater. Plug it into a pass-through thermostat like the Inkbird ITC-308 Plug and Play Temperature Controller, which is digital. The Inkbird is easy to use and to adjust. For instructions on how to set the Inkbird with the °CoolBot, check out our blog post “How to set up your cooler for the winter season.” A second option is the DuroStat Portable Waterproof Prewired Thermostat from FarmTek.com (Item #CR2045). This one is not digital like the Inkbird. Some of our customers (particularly for micro-brewing) have used the AGPtek STC-1000, but this is not a plug and play like the other ones. Make sure you choose a thermostat that can be set below 40°F!
Whichever thermostat you choose, we recommend setting the °CoolBot at least 4°F warmer than the heater so they don’t overlap and fight with each other.