How to Prepare Your CoolBot and Your Cooler for Spring

Spring is here! As we all roll up our sleeves to get ready for the season, till in the cover crop, seed trays and get those first transplants into the field, there’s one other chore to add to the list: cooler prep.

Making sure your cooler is ready to work for you is quick and easy and can help ensure a smooth start to the season. We recommend going through this checklist two weeks before using the cooler, allowing enough time to work out any kinks and be sure the system is ready to run.

How to Prepare Your Cooler for Spring | Cooler and A/C

First, make sure nobody has moved in over the winter, not just in the cooler, but in the a/c as well. Every once in a while, an industrious squirrel or mouse may find the a/c a tempting place to make a nest.

To do this, unplug the a/c, pull it out of the cabinet, and give it a thorough cleaning. Blow out all those leaves it may have collected with an air compressor or a shop vac. Be careful to not bend the fins!

You’ll want to make sure the front fins are clean too. Use a cup of plain, non-soapy water (soap can leave behind residue) and a long stiff-bristled brush. Dunk the bristles in the water and swipe down the fins. Keep rinsing and working your way across the front, changing out the water if it gets murky, until all the fins are clean. This should be done once every week or two throughout the season to keep things running smoothly.

Here’s a video of how to clean the fins:

If the fins are looking particularly rough, you can use foaming coil cleanser to help cut through the grime. Be sure to follow the directions on the label.

When you put the a/c back in, be sure it has that small tilt back and is level from side to side.


Now that the cooler and a/c are clean, let’s check on the CoolBot.

Plug in the CoolBot.

Make sure all the wires are in good condition and in the right place.

The Room and Fins sensors are black or blue wires with black ends and the Heater is a black wire with a red end.

Next, make sure the sensors are calibrated correctly:

  1. Let the Fins sensor hang next to the Room wire so the tips of them are side by side.
  2. Give them 30 seconds to acclimate.
  3. Note what temperature the Room sensor is reading, and then press the right arrow.
  4. The light under Fins should come on and the Fins temperature will now be displayed. Use the arrows to toggle back and forth.

Here’s a video on how to perform a quick calibration test:

The readings should be within a degree or two of one another. If they’re not, then you’ll need a replacement wire (if you have a separate thermometer, use that to determine which is correct).

You can order wires here.

If your CoolBot is within warranty, give us a call at 888.871.5723 or send us an email at with the best address to ship to.

*If you get a reading of Er or Ef, first make sure you have the right wires plugged in.

The sensors are either blue with black tips or black with black tips.

Unplug and plug the wire back in 2 to 3 times to make sure it’s fully seated.

If it’s still showing Er or Ef, then you’ll need a new wire.

Now that the sensors look good, let’s move on to the Heater.

You want to make sure it is getting hot. There is an easy test for this.

  1. First make sure the right wire is plugged in. The Heater is the black wire with a red tip.
  2. Unplug and plug the wire in 2 to 3 times to make sure it’s fully seated.
  3. Hold the red end of the Heater to the inside of your wrist (it doesn’t get very hot, so it can be hard to feel in your fingers).
  4. Then unplug the CoolBot’s power supply and plug it back in. Within the first 10 to 30 seconds, the red end of the Heater should get noticeably warm and the light in the bottom right corner next to Heater should come on solid.

Here’s a video on how to perform the heater test:

If the light comes on, then all is well. If it doesn’t, try doing a Hard Reset and then running the test again. Here’s how to do a Hard Reset:

  1. Press the right arrow to go over to Program. It should read something like 6.3 to 6.5.
  2. Press the center check mark button five times. It should now read “P1.”
  3. Press the center check mark button again, and it should show “n.”
  4. Press the right arrow to change to “y.”
  5. Press the center check mark.

Here’s video on how to do a Hard Reset:

Now, repeat the Heater test. If the light comes on solid, but there’s no heat, then you need a new Heater, which you can order here.

If your CoolBot is within warranty, give us a call at 888.871.5723 or send us an email at with the best address to ship to. Also contact us if there’s no light and no heat. We’d be happy to troubleshoot.

Now that you’ve checked all the wires, it’s time to make sure you have them set up properly.

  • The Room sensor should hang down freely, not touching anything metal and not in the way of the cold air.
  • The tip of the Fins sensor should be inserted 1/4″ into the fins of the a/c between the bottom two coolant lines.
  • The Heater wire should be wrapped up tightly using a 2″x2″ piece of normal kitchen foil to the a/c’s primary thermistor (and secondary if that applies).

Also take this opportunity to make sure you have the CoolBot set to the right settings. The system is designed to remember all your settings from last year. To check or adjust the Room temperature:

  1. Press the center check mark once. It should blink the current set temperature.
  2. Press the right arrow to raise and the left arrow to lower the temperature.
  3. When it reaches the desired setting, press the center check mark to set into memory.

Here’s a video on adjusting the settings:

Now let’s take the cooler for a test run! Plug in the a/c and set it to Cool mode, the lowest temperature, and the highest fan speed. Let the cooler run for a test period of 24 hours, and place some buckets of water or non-perishables in your cooler to add mass (empty coolers can fluctuate in temperature).

If, after 24 hours, the cooler is down to the right temperature, then you can shut everything off. When you are ready to use it, plug it in a couple of hours before loading it up to give it time to chill.

If the cooler is not cooling properly or if you’re having any trouble, give us a call at 888.871.5723 or send us an email at and we’d be happy to help.

Have a wonderful season and happy farming!

Comments 2

  1. planning to put up a 40′ shipping container as cooler for fruit (apple and pear), what suggestion you can provide me before I purchase coolbot or put in insulation etc..
    please response asap.

    1. Post

      Hi Oriana, We have a number of clients who will use shipping containers as the shell for their coolers and they work great! Often they need insulation added to them so we can reach our target R25. We have lots of information on our site here, as well as a free downloadable guide to building out a cooler here: Please let me know if you have any questions or need any help sizing, feel free to email us at or call our toll free line 888.871.5723.

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