ebay aquarium temp controller build

cwi said:

"Probe in air" is NOT the way to do it, especially for fermenting beer. It will kill your compressor and also not keep ferm'ing beer temps stable.

You may have your probe too well insulated which prevents the ambient from influencing the probe and causing an early shutoff (hysteresis compensation). You may also have to probe in an area that gets more residual cooling. A small computer fan can help.

Your heater sounds oversized. You only need ~40 watts. Also, why is your heater even plugged in? I know you are probably proud of the job you did wiring it up and all, but it's July!

I have a feeling that the beer temp isn't varying as much as the probe temp, and the low temps at the probe are being warmed by both the beer and the heater heating the air.

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All of the above is true.

The "probe in air" is not how I ferment. Just data I took when checking out the chamber performance before actually using it for a fermentation.

I have a 60W infared reptile lamp with fan. Fan kicks on with lamp. No fan for cooling.

Also, by the therm stuck on side of carboy, beer temp isn't flucuating as much as probe temp. Beer temp is about a degree or two F above the setpoint, per the stick-on thermometer.

Options I'm thinking of pursuing:
- Better insulation for probe to more accurately read beer temp.
- fan for cooling. This will be a no brainer given the way I wired by chamber.
- widening the deadband on the controller.

mikeysab said:

mine did the same thing when I had the probe taped to the bucket. It would cool about .5 to .8 below the set point. It would hit the temp, shut off, then continue to cool. While I was experimenting, I put two computer fans blowing away from the freezer section and left the probe dangling at the furthest point from the freezer. It worked much better this way. It cooled quicker, and didn't go much past the set point....only .2 or .3. So I guess instead of taping the probe to the bucket, I'll leave it dangling and compensate 5 or 6 degrees for fermentation heat.

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The important temperature is the temp of the beer, not the air. The beer was not cooling as far past the setpoint as the probe was (which is the temp you were looking at). The probe is influenced by the air AND beer, the proportion of which is largely dependent on the amount of insulation covering the probe.

Fans will help, but aren't really necessary for fermenting. For a collared keezer they should be mandatory.

If you choose to dangle your probe and compensate, do you think your ferming beer temps will be more accurate than .5-.8 (and it is really less) swing you get with it taped to the fermenter? Don't forget that the reaction heat varies, so keep your cot close to your ferm chamber so you can check what your current offset needs to be.

Boodlemania said:

- Better insulation for probe to more accurately read beer temp.

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Too much insulation on the probe can cause MORE hysteresis. The goal is to allow the ambient air to influence the probe slightly to cause an early shutoff of the freezer. In reality, the thermal 'inertia' of the evap coils of a normal sized freezer is small compared to the thermal mass of the beer. If your freezer is large, adding passive thermal mass can help. Your freezer should never be run empty, it cycles too much that way.

Boodlemania said:

Also, by the therm stuck on side of carboy, beer temp isn't flucuating as much as probe temp. Beer temp is about a degree or two F above the setpoint, per the stick-on thermometer.

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Stick-on "mood ring" thermos are ballpark only. They are influenced more by the air than your insulated probe. They just change slower.

Boodlemania said:

Options I'm thinking of pursuing:
- Better insulation for probe to more accurately read beer temp.
- fan for cooling. This will be a no brainer given the way I wired by chamber.
- widening the deadband on the controller.

Click to expand...

Maybe add:
- Unplugging the heater when the garage is above 100F.

Out of curiosity, has anyone used a standard, old computer power cord? Is the gage adequate for this application?

Example:

Boodlemania said:

Also, by the therm stuck on side of carboy, beer temp isn't flucuating as much as probe temp. Beer temp is about a degree or two F above the setpoint, per the stick-on thermometer.

Click to expand...

Did you have the carboy full of liquid during your testing? It will make a huge difference in the temp swings of the probe. Your heater coming on, even with a .5C diff doesn't seem right. A 5G vessel of liquid shouldn't change temp that much just by the residual heat (cold) in the coils.

barrooze said:

Out of curiosity, has anyone used a standard, old computer power cord? Is the gage adequate for this application?

Example:

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I used an old one I had in a spares box, but it depends on the cord. Most are marked on the sheath with the gauge. I have seen anywhere from 18ga to 12ga for server/computer cords. I think 14ga is the "official" minimum recommended for this.

I jumped on the bandwagon and ordered one also, however mine is for F not C. Looks like the connections are a bit different as well. It goes like this

\ _ \
Loading Power Function Probe

I would think loading is the relay, power is for 110v in, probe is obvious. However how do I wire up the function? The directions really don't have anything listed on wiring.

can be found here.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150606638066&ssPageName=STRK:MEWNX:IT

cwi said:

I used an old one I had in a spares box, but it depends on the cord. Most are marked on the sheath with the gauge. I have seen anywhere from 18ga to 12ga for server/computer cords. I think 14ga is the "official" minimum recommended for this.

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It seems like i have a dozen of these at home, so I'll definitely be checking the gage on the sheaths when i get home. Thanks!

cwi said:

Maybe add:
- Unplugging the heater when the garage is above 100F.

Click to expand...

As I stated in an earlier post, the ambient temp around my chamber, which is in my basement, is ~ 70F.

As for your other comments:
- the carboy was full.
- I realize stick-on therms are not highly accurate, NIST-traceable devices, but instead have inherent inaccuracies.
- I also realize that freezers/fridges are more efficient the more thermal mass they hold. To that end, I have extra mass in my chamber.

Thanks for the comments and ideas.

CoalCracker said:

I jumped on the bandwagon and ordered one also, however mine is for F not C. Looks like the connections are a bit different as well. It goes like this

\ _ \
Loading Power Function Probe

I would think loading is the relay, power is for 110v in, probe is obvious. However how do I wire up the function? The directions really don't have anything listed on wiring.

can be found here.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150606638066&ssPageName=STRK:MEWNX:IT

Click to expand...

The bandwagon you seemed to have jumped on is the one with the all the people who buy one of the ones that is $1 less than the model recommended in this thread. They end up with anything from 220v models, single stage, heat only, etc.

My guess is that putting a jumper, or not, between the two converts it to/from heating or cooling, or vice versa. Or maybe doing this makes a cool blue bolt of lightning followed by smoke- single use only for this function. Hard to tell without documentation. Maybe post the instructions.

If your controller has no short cycling prevention (ASD, compressor delay), be very careful when first setting it up in the fridge/freezer, and always have the probe on/in something thermally massive.

Didn't do it to save money. Didn't notice it was different until I got it. They don't list anything about wiring it. I do pretty good with wiring, this one has me a bit confused.

Boodlemania said:

As I stated in an earlier post, the ambient temp around my chamber, which is in my basement, is ~ 70F.

As for your other comments:
- the carboy was full.
- I realize stick-on therms are not highly accurate, NIST-traceable devices, but instead have inherent inaccuracies.
- I also realize that freezers/fridges are more efficient the more thermal mass they hold. To that end, I have extra mass in my chamber.

Thanks for the comments and ideas.

Click to expand...

If your basement is a steady 70F (not 100F like in my smart ass comment), you still shouldn't need a heater in your ferm chamber, unless you are doing a beer that ferms above 70F. In those cases you can add the heater for just those beers, and maybe even turn the fridge off. In a basement environment, you will only need both heating and cooling during the seasons when your ambient is below the ferm temp, but above the offset needed to compensate for reaction heat. In a garage environment, the temps can pass through these points in a single day, depending on the season.

These dual stage controllers are not sophisticated enough to maintain a .5C diff without the chance of oscillating heating/cooling. The oscillation may actually maintain a tighter beer temp, however it would be wasteful of energy and cause more cycling of your compressor. One guy's solution is to chill his chamber well below desired temps, then use a heat belt to maintain beer temps. He can ferm multiple batches simultaneously using this method.

Your original post was about cooling/heating battles and how to fix them. Removing the unneeded heater is one of the few solutions that will do that without increasing ferm temp swings. If you don't mind greater temp swings, then setting a larger diff will solve the problem.

I still find it strange that you have that much carryover registering at the probe, even though you have additional mass in the chamber. Maybe the probe is being affected by the coils (-25C) more than the air (5C). Try rotating the vessel so the probe is away from the coils. This may help by it being affected less by the carryover in the coils, and more by the beer temp.

CoalCracker said:

Didn't do it to save money. Didn't notice it was different until I got it. They don't list anything about wiring it. I do pretty good with wiring, this one has me a bit confused.

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It can't hurt to wire it up with nothing on the function pins, and see how it behaves. Nothing bad/permanent should happen with the pins open.

If the included manual doesn't have a schematic, and it's all you have to go on- it's time to put your reverse engineering hat on.

CoalCracker said:

Didn't do it to save money. Didn't notice it was different until I got it. They don't list anything about wiring it. I do pretty good with wiring, this one has me a bit confused.

Click to expand...

FWIW what you have is a single stage controller, and switching between heating and cooling is done in the programming menu, not by changing the wiring. It will work fine without wiring anything to the "function" terminals. I keep meaning to put a multimeter on it and figure out what if anthing the function terminals do, but haven't gotten around to it.

JuanMoore said:

FWIW what you have is a single stage controller, and switching between heating and cooling is done in the programming menu, not by changing the wiring. It will work fine without wiring anything to the "function" terminals. I keep meaning to put a multimeter on it and figure out what if anthing the function terminals do, but haven't gotten around to it.

Click to expand...

Great! Easy enough, pretty sure I did read that it can be wired to a refrigerator. So I take it you have the same unit?

CoalCracker said:

Great! Easy enough, pretty sure I did read that it can be wired to a refrigerator. So I take it you have the same unit?

Click to expand...

Yes it can be used to control a fridge. The programming is very easy, just push a couple buttons to switch back and forth between heating and cooling mode. I have 5 controllers total, three like yours (one in my keezer and two in my HERMS control panel), and two STC-1000's for my ferm chambers. The ones like yours are only single stage, but my keezer and control panel don't need dual stage and I was able to get them way cheaper than more STC-1000's would have been. I also prefer the SS probes on the single stage units much more than the plastic ones on the STC-1000.

This thread is huge! I've been trying to sort through it to see if I can find my answer, but I haven't had any luck so I figured I'd throw this out there. I just ordered one of these for my keezer project, but being relatively inept at figuring out wiring, I'm hoping someone can lend me a hand.

1) Do I need to wire up for both heating and cooling? If I just wire for cooling and plug the freezer into that outlet (or just wire a single outlet) would it still work? Or do I need some sort of heating element?

2) What kind of fan can I wire into it so that it come on only when the compressor comes on? Will a standard PC fan work? And do I just splice the wire in with the wires for the outlet to run the freezer?

Thanks in advance for any help you who are more knowledgeable might be able to offer!

Barnacle said:

This thread is huge! I've been trying to sort through it to see if I can find my answer, but I haven't had any luck so I figured I'd throw this out there. I just ordered one of these for my keezer project, but being relatively inept at figuring out wiring, I'm hoping someone can lend me a hand.

1) Do I need to wire up for both heating and cooling? If I just wire for cooling and plug the freezer into that outlet (or just wire a single outlet) would it still work? Or do I need some sort of heating element?

2) What kind of fan can I wire into it so that it come on only when the compressor comes on? Will a standard PC fan work? And do I just splice the wire in with the wires for the outlet to run the freezer?

Thanks in advance for any help you who are more knowledgeable might be able to offer!

Click to expand...

1) yes, you can use just cooling if you want.

2) DO NOT wire a PC fan directly into the same power as the freezer. It needs to be converted to 12V DC (or a bit lower, which will just slow the fan down). One way you could do this is wire a duplex outlet to the cooling, run the freezer from one outlet, and then wire a fan from into a wall-wart AC adapter (something like a cellphone charger), and plug THAT into the other outlet.

JuanMoore said:

Yes it can be used to control a fridge. The programming is very easy, just push a couple buttons to switch back and forth between heating and cooling mode. I have 5 controllers total, three like yours (one in my keezer and two in my HERMS control panel), and two STC-1000's for my ferm chambers. The ones like yours are only single stage, but my keezer and control panel don't need dual stage and I was able to get them way cheaper than more STC-1000's would have been. I also prefer the SS probes on the single stage units much more than the plastic ones on the STC-1000.

Click to expand...

I wired it up and the relay clicks but doesn't turn the light on or off. I put the white and black in the power and the switching, then tied the ground together. Is this right?

CoalCracker said:

I wired it up and the relay clicks but doesn't turn the light on or off. I put the white and black in the power and the switching, then tied the ground together. Is this right?

Click to expand...

It's hard to tell from your description, but I don't think that's right. I'll draw something up and post it here shortly.

It should look somthing like this. You can also swap the hot and neutral so that it's the hot that gets switched instead of the neutral.

Barnacle said:

2) What kind of fan can I wire into it so that it come on only when the compressor comes on? Will a standard PC fan work? And do I just splice the wire in with the wires for the outlet to run the freezer?

Click to expand...

I just used a small, four-inch fan that I picked up in the automotive section (which is where all of their fans are stocked). It was $6.99, runs on AC, and get plugged into the same receptacle that runs the keezer, so it runs when the keezer runs.

hey guys, quick question. will the average mini fridge hold a temp around 60-65 without a temp controller? i know that's warm for a fridge. i can get one for a decent price but am doubting my ability to hook up a temp controller.

MrManifesto said:

hey guys, quick question. will the average mini fridge hold a temp around 60-65 without a temp controller? i know that's warm for a fridge. i can get one for a decent price but am doubting my ability to hook up a temp controller.

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I'm not sure. Some of them can take thermostat out and turn a hidden screw to raise the min/max temperatures, but IMO, a controller is still easier, and much more precise (and pretty essential if you're using it to ferment in rather than to chill kegs).

It's easier than it sounds, and there's a first time for everything, you know? Homebrewing projects like these have pushed me to learn some DIY skills I didn't have before... and if you have any questions, plenty of people are here to help you out!

MrManifesto said:

hey guys, quick question. will the average mini fridge hold a temp around 60-65 without a temp controller? i know that's warm for a fridge. i can get one for a decent price but am doubting my ability to hook up a temp controller.

Click to expand...

I just got a mini fridge off Craigslist and even on minimum it will go down into the low 40s

here is pic of mine...

I just set mine up using a 6x6x4 from Home Depot and a 15 cf chest freezer. After the 3 minute delay, it started right up!

Ok this controller off of ebay, the 110v version, i plan on using it for a aquarium now here is my question can you set it were the cold side comes on at say 84° but the heat side does not come until it reaches say below 76°? Can both sides have there own setting? Also i dont know if anyone has done this yet as i am not reading that many pages but i am going to add a relay to my cold side to make stuff like my heat building aquarium lights shut off as well when the cold side comes on.

I don't believe this particular unit can do two different temps.

downtime89 said:

Ok this controller off of ebay, the 110v version, i plan on using it for a aquarium now here is my question can you set it were the cold side comes on at say 84° but the heat side does not come until it reaches say below 76°? Can both sides have there own setting? Also i dont know if anyone has done this yet as i am not reading that many pages but i am going to add a relay to my cold side to make stuff like my heat building aquarium lights shut off as well when the cold side comes on.

Click to expand...

usfmikeb said:

I don't believe this particular unit can do two different temps.

Click to expand...

It has a setting for the deadband (I think thats the name for it) to a max of 10 degrees C. So if you set it at 80 deg. F with a deadband of 12 deg. F I think it should do what you want (you will have to set it in degrees C though )

If I order this from the seller that states they ship 110v to countries that use it and 220v to countries that use that, will i get 110v or are there alot of screw-ups in this department?

Anyone with experience?

I live in Atlanta GA and mine came in the correct voltage.

mattd2 said:

It has a setting for the deadband (I think thats the name for it) to a max of 10 degrees C. So if you set it at 80 deg. F with a deadband of 12 deg. F I think it should do what you want (you will have to set it in degrees C though )

Click to expand...

can someone test this theory for me before i order one? say set a temp to heat up tp 76 and stop then cool if it hits 84. So set a dead band of 8 degrees between 76 and 84 is that right matt2d?

downtime89 said:

Ok this controller off of ebay, the 110v version, i plan on using it for a aquarium now here is my question can you set it were the cold side comes on at say 84° but the heat side does not come until it reaches say below 76°? Can both sides have there own setting? Also i dont know if anyone has done this yet as i am not reading that many pages but i am going to add a relay to my cold side to make stuff like my heat building aquarium lights shut off as well when the cold side comes on.

Click to expand...

The STC-1000 is programmed using one set value and one differential value for both heating and cooling. The way this works is that when the probe temp reads the set value plus the differential value, the cooling relay is activated and stays on until it reaches the set value. When the probe reads the set temp minus the differential, it activates the heat relay and stays on until the set temp is reached. To do what you're describing you'd simply put the set temp at 80, and the differential at 4. This would activate cooling at 84, keep cooling until 80, activate heating at 76, and keep heating to 80. I'm guessing you're referring to degrees fahrenheit though, and this controller is celcius. Converting to celcius, you'd want to put the set temp at ~26.7C and the differential at ~2.2C.

BrewForMe said:

If I order this from the seller that states they ship 110v to countries that use it and 220v to countries that use that, will i get 110v or are there alot of screw-ups in this department?

Anyone with experience?

Click to expand...

Most have gotten the right one if it had that wording in the listing, but it's probably a good idea to write a reminder that you need the 110v version in the notes section when you pay.

lol its for a aquarium.

Can someone who's gone through this whole huge thread help me out here?
I'm looking for a schematic to wire this controller and have a small 12VDC PC fan turn on whenever the heating or cooling relays are active.
I understand I would likely need a separate relay to do so. To get the 12VDC from a wall-wort or some other type of power supply to the fan... Just curious what type of relay I'd need and where to wire the coil(s) to.

krazydave said:

Can someone who's gone through this whole huge thread help me out here?
I'm looking for a schematic to wire this controller and have a small 12VDC PC fan turn on whenever the heating or cooling relays are active.
I understand I would likely need a separate relay to do so. To get the 12VDC from a wall-wort or some other type of power supply to the fan... Just curious what type of relay I'd need and where to wire the coil(s) to.

Click to expand...

I thought about that too (wiring it into both would have the effect of the heat relay turning on the cooling device, and vice versa), but I ultimately decided that the fan really uses such low wattage, and that it will still provide a small benefit, that I was better off just providing the fan an"always on" power source.

JuanMoore said:

The STC-1000 is programmed using one set value and one differential value for both heating and cooling. The way this works is that when the probe temp reads the set value plus the differential value, the cooling relay is activated and stays on until it reaches the set value. When the probe reads the set temp minus the differential, it activates the heat relay and stays on until the set temp is reached. To do what you're describing you'd simply put the set temp at 80, and the differential at 4. This would activate cooling at 84, keep cooling until 80, activate heating at 76, and keep heating to 80. I'm guessing you're referring to degrees fahrenheit though, and this controller is celcius. Converting to celcius, you'd want to put the set temp at ~26.7C and the differential at ~2.2C.

Click to expand...

So if the heat is set at 80 the heater not kick on at 80? i think a reef aquarium would have alot of issues going from 76-80 back and forth all day long. Altho i it shouldnt go over the set heat very often.I am going to have fun seeing if i can make this work... lol