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Possible coolbot alternative for $35

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porterpounder

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The thing about the coolbot is the frost sensor and heater that tricks the AC into not freezing solid. I have and 8x8 walk-in cooled by a 12000 unit controlled by a gen 1 coolbot and it has been flawless with continuous operation for 3 years until a few weeks ago and the fix was quick, easy and I was back up like nothing happened in a day. Ron, the designer, was extremely helpful and responsive in fixing the problem. Hassle-free customer service like that along with a great product is worth the cost in the long-term IMO.
 

onthekeg

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It will heat or cool, but it doesn't appear to do both since it only has one controlled plug in. IE if the freezer is plugged in, it won't be able to run a heater.
 
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wilfonzo

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I hadn't thought of the a/c unit freezing. I think I'll buy it and give it a shot. My fermentation chamber is only a 5'x3' and 3' tall shower in the garage I insulated and use a window unit to cool. The setting on the a/c only goes down to 66 which keeps the chamber at 71* this time of year. I'm afraid that the 90* summer weather will be too much for it. I really only want to keep it at 65* since all I only do ales. Whenever it arrives I'll post more info on how it's working.

The chillbot seems like a pretty awesome unit, but if I'm dropping $300 it is going to be on a larger fridge.
 

onthekeg

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Couldn't you just run the A/C unit to 66 and let it go then? Why do you need this? It won't make it any colder. You need to put this on a refrigerator or freezer to get colder than you can with the AC unit.
 
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wilfonzo

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I keep it set to 66* and the actual ambient temp inside the cooler is only getting as low as 70* with 80-85* weather. I will be adding more insulation before summer also.
 

fortydegnorth

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Move the AC temp sensor to the outside of the cooled area. It will think it's still hot in the chamber when in fact it's only hot outside. Then control the AC with a ranco, aquarium controller or whatever you want. You can also trick the temp sensor with a night light or something to heat it up a little.
 
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wilfonzo

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Good idea, I ordered the controller above and will leave the sensor outside. I'm also going to have to do some major insulating, temps hit 74 inside the other day.
 

Eternalodyssey

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Honestly, I would just order the Coolbot and call it good. Too much research and development has gone into these products for me to second guess the results at the cost of a few extra bucks. Is it some bucks? Yeah. Is it worth to me when considering the extra hassle, work, missed brew days/sampling, meetings of not using a piece of technology such as the Coolbot? NO! My advice is to stick with proven technology. But that is just my advice. You have to make your decisions based off your needs/budget.
 

Durango_Doug

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I apologize for bringing this from the dead, but I have found that the coolbot is not necessary if you are willing to do some easy wiring.

An Inkbird ITC-308 would be more appropriate than the WIN-100. I have both. The WIN only cools down to 45 degrees, which is fine in your case, but the inkbird has a compressor delay, which is needed. Pulling the ac unit's temp probe away from the fins should allow cooler temps. Cooling down to 65 shouldn't create frost issues. I use an inkbird to cool below 40 degrees, and frozen fins are an issue at that temp. A coolbot isn't necessary if you don't mind doing some wiring. I bought two inkbird controllers and a contactor/relay ($90 total). I used the Emerson 90-245 120 VAC 30 Amp 2 Pole Definite Purpose Contactor. I wired the contactor to directly control the compressor, which allows the fan on the ac unit to stay on for defrosting purposes. At first I tried using a heater on the temp probe like the coolbot does, but you are definitely limited to certain ac units if you go this route. If you wire up to directly control the compressor, you can use any ac unit you want, and there is no on/off delay caused by using a heater on the temp probe. The two inkbird controllers are plugged into each other in series, and control on/off of the compressor. The temp sensor from the first inkbird is inserted into the cooling fins of the ac unit just like with a coolbot, allowing precise control of a defrost cycle based on fin temp and minimum defrost time. The temp probe from the second controller senses the room temp. The two controllers in series control the on/off cycles of the compressor by switching the contactor on and off. With this setup, the compressor only turns on if the room temp is over your set point, the fin temp is above a certain set point (32 degrees has worked for me), and a defrost cycle has been completed using the compressor delay setting for the controller sensing the fin temp. This setup is a lot cheaper than the coolbot, and works better than the coolbot because the delays in on/off control associated with using a heater on the ac units temp sensor are avoided. I actually use two ac units with this setup, running the compressor from each unit through the separate poles on the contactor. It doesn't take long to determine which of the two ac units frosts up first, and the temp probe for determining fin temp is inserted into that unit to control the defrost cycle. Using two unit gives a higher cooling ability, and shorter run times for reduced frosting issues. I've found that used 15k btu/hr units can be easily found for as low as $25. That's about as big a unit as they make without getting into a 240v unit.
 

Durango_Doug

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It took some tinkering to figure it out, but i refused to buy into the coolbot with all the cheap temp controllers available.
 

Durango_Doug

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I also played around with a Century Short Period Repeat Cycle Timer and heat lamps as a defrost method, but the defrost cycle times need to be altered based on changing run times, and it didn't work well. Fin frosting is largely determined by ambient temps, rh, and needed run times, so monitoring the fin temp is essential.
 

H20ENG

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Can do the same with 2 cheap thermostats if you're willing to do some wiring. 1 Tstat for your desired box set point. The other (in series) is strictly for frost control. Only wire the Tstats to the compressor. Leave the fan/blower on 24/7. Fiddle with the frost control Tstat setting to get it shut down when frost starts to build up. As soon as the compressor stops, the air blowing across the coil melts the frost and it can start back up in a few minutes, which is a good idea for compressor delay anyway. I built this setup for my brothers meat walkin and it's been running great for about 3 years, even with several fresh deer or hogs hanging in there. He's had up to 5 animals in there (sadly no beer) It cycles more at first while drying/cooling then doesn't take much run time.
Good advise: open the ac unit and try to plug any little holes. Air (heat and more so moisture) getting into your enclosure is the enemy. Likewise be sure your seams and door gaskets are tight. Also be sure and tilt the unit so it can drain the water out. It works!
 

Remi32

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If I just leave the fan/blower on 24/7 would that avoid the coils freezing? My plan is to buy the "Inkbird Itc-308 Digital Temperature Controller Outlet Thermostat" that has a plug for cooling and heating. My cooler is going to be in an unheated barn so afraid it'll actually let the meat freeze if below freezing too long outside. So when I had a deer in it....would leave the fan/blower running to avoid freezing. Then have it set so when it turned on the cooling plug at 40 degrees...it would turn on a nightlight that was taped to the thermocouple inside the AC to keep it running. And have it set to turn on the heater plug with a small heater if it dropped below 34 degrees or so just to keep the meat from freezing solid. I'm not an expert with electrical stuff so trying to keep it simple. Anybody see something with my plan where I'll run into problems?
 

Durango_Doug

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If I just leave the fan/blower on 24/7 would that avoid the coils freezing? My plan is to buy the "Inkbird Itc-308 Digital Temperature Controller Outlet Thermostat" that has a plug for cooling and heating. My cooler is going to be in an unheated barn so afraid it'll actually let the meat freeze if below freezing too long outside. So when I had a deer in it....would leave the fan/blower running to avoid freezing. Then have it set so when it turned on the cooling plug at 40 degrees...it would turn on a nightlight that was taped to the thermocouple inside the AC to keep it running. And have it set to turn on the heater plug with a small heater if it dropped below 34 degrees or so just to keep the meat from freezing solid. I'm not an expert with electrical stuff so trying to keep it simple. Anybody see something with my plan where I'll run into problems?

A little late, but yes there are some problems. If using the heater plug to trick the AC into running, you must use specific ac units; namely, those suggested by coolbot. Other units will have such a long delay using that method that it's essentially ineffective. I would just plug an electric oil filled radiator or heat lamp into the heating side of the thermostat to keep the room from freezing. You're biggest problem here is that you can't just leave the ac fan running to keep the fins from icing up. Once the room starts to get somewhat cold, it only takes 2 or 3 minutes for the fins to ice up. You have to have a way to shut the compressor off intermittently, and having the thermostat monitor the fin temp as well as room temp is the best way to do that. I did this by running two itc-308 stats in series. There are other ways too, as H2OENG mentioned. You'll find that if you don't monitor fin temps, your system will not be reliable.
 

H20ENG

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We find that with fresh meat (deer, hogs), obviously there's a lot of moisture introduced. A desiccant dryer or electronic dehumidifier works great to help remove moisture and allow the unit to spend more time cooling than defrosting.

With beer, you should only be up against the moisture from the air you let in when opening the door.
 

Durango_Doug

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Can I use the inkbird 1000 only and not two or them?
You could, but you'll be limited in how cold you'll be able to cool to. It's unlikely that you'd be able to cool lower than 50 degrees. And you'd definitely still have to use a heater on the fin probe, or control the compressor directly.
 

H20ENG

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You have to control frosting of the coils somehow. Using a 2nd tstat to defrost is the easiest way IMO.
 

ron.romanowicz10

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I am in vietnam. The electric here is 220v. Will the
Emerson 90-245 120 VAC 30 Amp 2 Pole Definite Purpose Contactor
Work here? If not, what should I use. Looks like I have to import all the parts
 

H20ENG

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The link doesn't work for me. You want to match a contactor coil voltage to what you have available. You can also get a contactor with a low voltage coil (12/24v) if you have a power supply or adapter and still switch your line voltage to the compressor.
How much current does your AC draw that you need to use a contactor?
 

mightymarooms

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I apologize for bringing this from the dead, but I have found that the coolbot is not necessary if you are willing to do some easy wiring.

An Inkbird ITC-308 would be more appropriate than the WIN-100. I have both. The WIN only cools down to 45 degrees, which is fine in your case, but the inkbird has a compressor delay, which is needed. Pulling the ac unit's temp probe away from the fins should allow cooler temps. Cooling down to 65 shouldn't create frost issues. I use an inkbird to cool below 40 degrees, and frozen fins are an issue at that temp. A coolbot isn't necessary if you don't mind doing some wiring. I bought two inkbird controllers and a contactor/relay ($90 total). I used the Emerson 90-245 120 VAC 30 Amp 2 Pole Definite Purpose Contactor. I wired the contactor to directly control the compressor, which allows the fan on the ac unit to stay on for defrosting purposes. At first I tried using a heater on the temp probe like the coolbot does, but you are definitely limited to certain ac units if you go this route. If you wire up to directly control the compressor, you can use any ac unit you want, and there is no on/off delay caused by using a heater on the temp probe. The two inkbird controllers are plugged into each other in series, and control on/off of the compressor. The temp sensor from the first inkbird is inserted into the cooling fins of the ac unit just like with a coolbot, allowing precise control of a defrost cycle based on fin temp and minimum defrost time. The temp probe from the second controller senses the room temp. The two controllers in series control the on/off cycles of the compressor by switching the contactor on and off. With this setup, the compressor only turns on if the room temp is over your set point, the fin temp is above a certain set point (32 degrees has worked for me), and a defrost cycle has been completed using the compressor delay setting for the controller sensing the fin temp. This setup is a lot cheaper than the coolbot, and works better than the coolbot because the delays in on/off control associated with using a heater on the ac units temp sensor are avoided. I actually use two ac units with this setup, running the compressor from each unit through the separate poles on the contactor. It doesn't take long to determine which of the two ac units frosts up first, and the temp probe for determining fin temp is inserted into that unit to control the defrost cycle. Using two unit gives a higher cooling ability, and shorter run times for reduced frosting issues. I've found that used 15k btu/hr units can be easily found for as low as $25. That's about as big a unit as they make without getting into a 240v unit.
I know this post already 2 years ago but may I ask where is the contactor connected? Hoping you'll answer my question. It would be better if you could provide a wiring diagram.
Thank you.
 
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I know this post already 2 years ago but may I ask where is the contactor connected? Hoping you'll answer my question. It would be better if you could provide a wiring diagram.
Thank you.
Well, what’s your end goal, walk in freezer or fermentation chamber for a 5gal carbon? I have a fermentation chamber I built a controller for that will do hot and cold. It uses a mini fridge and small space heater so it won’t do a whole room. I’ve done lagers at 45 degrees and a kviek at 95 degrees.
 

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