FAQ

Yes! We have a ton of independent data to suggest that using a CoolBot with a 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) study 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 a CoolBot-driven system is about 40% more efficient than a conventional refrigerator.

Although the CoolBot-driven system is typically oversized 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 tradeoff 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. If you can be judicious about minimizing door openings, we think you will save a bunch of money with the CoolBot.

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 ).

CoolBots can be set down to a target temperature of 32°F (0°C), but most customers use their CoolBots in the 38°F – 40°F (3.3°-4.4°C) range, which is where most veggies, meats, and prepared foods are recommended to be kept (most fridges are set at 38°F (3.3°C)).

As you push the cooler below 38°F (3.3°C), the A/C has to work increasingly harder. To the extent you want to push the temperature below 38°F (3.3°C), you can help by (a) increasing the A/C size, (b) decreasing frequencies of door openings, and (c) building an extremely well insulated cooler.

Most customers with an R25 insulated cooler hit 36°F without any issues. Customers getting their coolers below 36°F (2.2°C) have the best-insulated coolers (with insulated floors), open their cooler doors less frequently and almost all oversize their A/Cs vs. our recommendation to be conservative.

See our Temperature page for more information on the right temperature for storing your product.

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.

Mounting the CoolBot outside of the cooler is a very bad idea. 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 an indoor-outdoor thermometer.

Yes, we do ship internationally! CoolBots ship with international 110V / 220V power supplies so they run on all voltages with no transformer needed. CoolBots can display in either Celsius or Fahrenheit.

While window A/Cs are most common in the U.S., many users internationally find that “Split” or “Mini-Split” air conditioners are more readily available. The CoolBot works great on ductless mini-split air conditioners, and they are more energy efficient than window A/C units. .

The CoolBot works great with almost all known mini-split air conditioners (see our Air Conditioner Selection Guide). If you are concerned about how the CoolBot will run with a particular brand of air conditioner, please send us a help request with a web-link to the manufacturer including the model number, BTU’s, and preferably a link to the manufacturers’ brochure, and we can check it out. So far there have been practically no mini-splits that do not work with the CoolBot.

Please see our Shop Page for the latest shipping options to your destination.

When we first started the Company in 2006, we were really active about connecting people. Since then, we have over 30,000 installations, so there are multiple people near you in every state using a CoolBot. Unfortunately we don’t share customer names anymore for privacy and management reasons.

However, we do have a ton of customer testimonials. You can see testimonials for your specific use case on the following pages:

• Agriculture
• Bars
• Brewing
• Dairy
• Floral
• Hunting & Meat
• Mortuary
• Restaurants
• Wine Cellar

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.

Yes! There are options and we have customers using solar power to run their systems. The systems can be expensive due to the inverters and batteries. (The inverter is what converts the electricity from the solar powered DC to the standard air conditioner AC power.) The air conditioner can work like this, but the cost of batteries makes it significantly more expensive than a standard grid set-up.

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’re happy to help with any specific information for any one who wants to do it.

Sure! There are a few options:

1. Buy an extender from any electronics store; just be sure the plug fits exactly (2.5mm mono)
2. 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.

We do void the warranty on the sensor cable that you cut, but we don’t void the warranty on the CoolBot. If the splice doesn’t work, head to our Shop to purchase a new sensor.

It would be great if the CoolBot could work with analog, knob style A/C units, but unfortunately they don’t work. The CoolBot heater can’t overcome the mass of the metal capillary tube sensors that are present in A/C’s with knobs. The digital ones use low mass thermistors which are easy for our heater to work with.

We have a sizing and brand recommendation chart available on our Air Conditioner Selection Guide, but to figure this out for sure, it depends on a lot of factors including cooler insulation, ambient temperatures, the ground temperature where you live, if you are storing anything which produces heat, and if the cooler is indoors or out in the sunshine.

Fill in our Cooler Construction Advice Form and we will get back to you with the best size for your cooler.

Surprisingly it will not!

A CoolBot-driven A/C in a walk-in cooler will cycle way less than it will in a residential setting. A lot of cooling will be lost in a traditional residential setting because of significantly less insulation, sun streaming through windows, and cold air spilling into other rooms and escaping through gaps and cracks around doors and windows. Your compressor may wind up running 80% – 90% of the time.

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 report that the A/C compressor runs 10% – 15% of the time.

There are pros and cons of running the A/C in Energy Saver Mode. Here are the facts to consider:

Pros of running Energy Saver Mode:

• Saves a little 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 should 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, you need to change the HEATER Delay setting up to “d3” from the default of “d1”.

To do that, do the following:

1. 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)
2. Tap the CHECK MARK button 3 times (or until you see “d1” blinking in the display)
3. Tap the right arrow twice to change to “d3”
4. Press the Check mark once to lock in the new setting. The display reverts back to normal in 20 seconds.

Yes! The temperature will drop down faster, recover from door openings quicker, and be able to get colder than 36F. Additionally, you may actually save money in the long run even though you spent more for a larger air conditioner up front.

For example, our recommendation for an 8x8x8 room is 12,000 BTU’s:

• If you bumped up one or two levels 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 can 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). That could save you $15/month, which over a few years will have paid for the extra cost of the bigger air conditioner. A 15,000 BTU A/C is good, and a 18,000 BTU A/C is even better.
• If you wanted to go up three levels to 24,000 BTU’s, you wouldn’t save more money in electricity, but you could drop the temperature even faster and could go even colder. If you do want to upsize to 24,000 BTUs, be sure to fill out our Cooler Construction Advice Form and we can make sure you’re not oversizing the A/C unit.

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.

Yes! We have customers successfully using multi-zone mini split systems with the CoolBot.

You need to be sure the outdoor compressor 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 compressor 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. Regarding mini splits, just get an A/C with 13 SEERS and you will be set.

Yes! We have over 1,000 mobile applications running CoolBots including trucks, vans, box trucks, slide-in units in the back of pick-up trucks, boats and trailers. We do not recommend using an RV roof mount A/C unit as they don’t work well with the CoolBot. See below for some tips on building a mobile cooler.

Tips on Building a Mobile Cooler

1. Window air conditioners are actually pretty sturdy, and support from the outside always helps. Be sure to slope A/C downward in the back to offer drainage.
2. Since heat rises from the road, floor insulation is critical. Use R30 for the floor and R25 or more in the walls and ceiling. You cannot skimp on the insulation in a truck or trailer. Meticulously seal every gap and crack.
3. Insulation! We are super cheap and robust compared to other mobile cooling solutions, but do not underestimate the importance of the proper insulation.
4. You can run off the alternator on your vehicle if you buy a 12,000 BTU air conditioner or smaller and an inverter. For spaces up to 8×6 that are very well insulated, you should be able to hold 38°F.
5. For a very good inverter here’s a link to Amazon: Tripp Lite Heavy Duty Inverter. Generally you want an inverter that can surge to 3 times the running watts listed on the air conditioner
6. For larger box trucks and trailers where you need a 15,000 BTU or higher A/C, you will need to upsize to a much more expensive, non-commodity inverter and alternator. Alternatively, you can save some money and use a generator.
7. If the A/C and generator are too closely matched on wattage and there is barely enough power for the initial surge, you can get a hard start capacitor.
8. For short trips where the door won’t be opened, some people can get away with chilling everything first, unplugging the A/C and CoolBot, driving to the destination, and plugging everything back in. A well built cooler will maintain its temperature for a while.

Critical How-To Information

• For mobile applications, we only recommend polyisocyanurate rigid foam insulation or closed cell spray foam (or a combination.) Layer it till you have R25 in the walls / ceiling and R30 in the floor.
• Use urethane spray foam like “Great Stuff”, but avoid the latex version.
• Professionally installed closed cell spray foam insulation is R7 per inch at best, so make sure you get enough layers in if you decide to go that route.
• You can use glue to hold rigid foam insulation in place. We use 3M high strength 90″ adhesive spray.

Why RV Roof Mount A/C Units are a Bad Choice

Aesthetically an RV roof mount air conditioner is tempting, but here are some reasons we don’t recommend them:

1. They are really expensive per BTU versus window units.
2. They are annoying to set up, because you are working over your head and up in a hole with no sight line. It is therefore difficult to put our Fin Sensor in place correctly. Even worse, you won’t know if the Fin Sensor has fallen out unless you look with a mirror and flashlight.
3. Because of the very limited area they are sucking and blowing out of (14″x14″ for many cases), there is a BTU-transfer penalty of almost 30% if you buy a 15,000 BTU unit. It therefore only puts out 10,500 BTUs of cooling capacity! This makes RV A/C units even more overpriced.
4. For all these reasons, it’s not easy to get below 40°F with an RV air conditioner

Yes! We have thousands of hunters and many small commercial meat processing facilities using CoolBots to keep their meat cool. You need to correctly size the air conditioner according to our Air Conditioner Selection Guide and you need to have R25 waterproof insulation in the walls, floor and ceiling (covering the wood studs) with no gaps or cracks.

What the CoolBot can not do is:

• Keep things frozen
• Keep things cold when you have a substandard cooler, too small of an air conditioner or a poorly insulated room

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!

There aren’t any NSF certified air conditioners, so no restaurants with an air conditioner in their commercial kitchens have them NSF certified.

We are running in thousands of inspected commercial kitchens and inspected meat processing operations with no problem. Many people also build their own coolers and use FRP (fiberglass reinforced panels) on the inside. There are NSF certified walk-in cooler panels. You can check with your local department to find out if that’s necessary.

One inspector was concerned that the CoolBot was not NSF certified. Our controller is legally classified as a thermostat, and there are no NSF certified thermostats. It is of course okay to have a thermostat in a kitchen (even smart programmable thermostats). One compromise could be to have a NSF certified thermometer to track the temperature.

The best thing to do is ask your local inspector ahead of time. We have 30,000+ units out there, thousands of which are in commercial kitchens. We would be happy to speak with a local inspector who is concerned or questioning the idea.

See our handy A/C Sizing Chart for some tips on the correct temperature to store your product!

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!

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.

The humidity level with a CoolBot and air conditioner usually ends up in the 80% – 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 80% – 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 80% – 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.

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 upsizing the air conditioner a little).

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.

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 80% – 90%.

If you want higher humidity levels, you can add a vapor humidifier with a humidistat into the cooler. It will not affect the function of the CoolBot or air conditioner.

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 running 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:

1. 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).
2. 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.
3. 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.
4. 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.
5. Use chemical desiccants:
   1. 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.
   2. 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!