The Auber SYL-1615 is a highly-configurable thermostatic controller for charcoal cookers. It can be operated by merely setting the target temperature, mounting the blower (no tools required), inserting the temperature probe, and standing back while it does all the work. It does an excellent job regulating the temperature using the default configuration, but it can be tweaked to an extent that an electrical control engineer would love. (I'm that kind of guy!) The test results presented here use the default settings.
The idea behind a controller like this is to regulate the temperature inside the cooker by adjusting the airflow. The more air, the hotter it gets. A temperature probe clipped to the grill grate and routed out of the cooker to the controller provides the feedback needed to make airflow decisions. It's a lot more complicated than that, but that's all you really need to know to use this device.
Test Procedure: This product was tested on an 18.5" Weber Smokey Mountain. I loaded 2 lbs. of Kingsford Competition Briquets into the cooker, and lit 1 lb. of the same charcoal in a chimney, and poured it on the unlit coals already in the smoker. The water bucket was about 2/3 full, and there was no food in the cooker. (Shoot me!) The blower was attached to one of the lower vents, and the others were closed. The temperature probe was clipped to the center of the top cooking grate. Another temperature probe was mounted close to the sensor and plugged into a ThermoWorks BlueTherm Duo that was monitored on my computer for temperature recording purposes. The set temperature was 225ºF, consistent with smoking practices.
The outside air temperature was from 90 to 108ºF. Winds were light and variable. Measurements began shortly after the smoker was closed up. The charcoal burned for a little over four hours before the blower began to run full-time, signaling that the fuel was nearly exhausted. At that point, I terminated the test. The captured data from the ThermoWorks sensor was plotted, and the raw data was exported to Excel so that I could calculate temperature maxima, minima, average and standard deviation. The last value gives a measure of how consistent the temperature remained. If the temperature was dead constant, the standard deviation would be zero. The larger the swings in temperature, the higher the standard deviation would be. The values for this test are:
Maximum temperature: 228ºF
Minimum temperature: 215ºF
Average temperature: 222ºF
Standard deviation: 2.0ºF
At one point during the test, around 11 o'clock, I jostled the smoker to dislodge ash from the coals. This gives rise to a spike in the temperature that the thermostat must compensate for. This occured around the mid point of this test.
The graph of temperature versus time was converted to a jpg image so that you can view how consistent the temperature was. (Click on graph to see a larger version of the file.) Keep in mind that the data extends beyond the time when the charcoal was essentially exhausted, so you can ignore the decline on the right side of the graph. The spike that occured just before the coals expired makes the graph look more erratic than it would be in normal cooking because you would add more fuel than you need to complete the cook. Overall, the Auber did a fine job of regulating cooker temperature.
For those who wish to refine the performance of their thermostat, the owner's manual explains how to access the various parameters that are used to control the mathematical algorithm that controls the cooker. You can run it through an auto-calibrate procedure where the controller determines the optimum settings for your cooker configuration. You can calibrate the probe used to supply the temperature feedback. You can also set upper and lower alarm thresholds.
This test was conducted using the 6.5 cfm blower and the standard temperature probe. The controller will accept any k-type thermocouple probe that uses the standard two-pronged plug, so if you have some other probes, you can use them as well.
This is one of the best performing thermostatic controllers I've tested, and it's also the lowest price unit. That's an unbeatable combination! This model does lack the ability to connect to your computer/smart device, so if you need that capability, you might need to keep searching. On the other hand, do you really need to plot graphs and calculate standard deviations? Probably not - it's just food, after all.
I give this unit a solid Gold medal for stellar performance at a bargain price. You'll wonder how you ever lived without one of these things once you've used one.
The manufacturer of this product explains how the user can run an "auto-tune" cycle to allow the controller to "learn" the behavior of the cooker being used. This learning modifies some parameters that are used in the control equations to regulate the fan output. In theory, a controller that is tuned to a particular cooker being operated under a given set of conditions will perform better than one set up with generic settings. I decided to test this auto-tune feature on the Weber Smokey Mountain cooker that I was using in this test. I set up pretty much the same way I did in the earlier tests, except that I used 3 lbs. of charcoal instead of 2. The ambient conditions were close to those encountered earlier. I got the smoker up to about the right temperature by letting the fan run, and then I initiated the AT (auto-tune) sequence. In the graph below (click on it to see a larger version), the temperature swings at the beginning of the test are the result of the tuning procedure, which basically turns the fan on if the temp is below 215ºF and turns it off when the temp is above this value. The fan turns on when the temperature is dropping, and it takes about five minutes of full-on fan to reverse the drop and cause the temperature to rise. When the fan shuts off, the temp continues to rise, peaks, then begins to fall. This cycle tells the controller how quickly the cooker responds to the fan, and the controller then adjusts its parameters to fit the cooker's characteristics.
In order to tell how well the controller worked after the auto-tune cycle completed, I ran the test until the smoker ran out of fuel around 2 p.m. I exported the data that represented the running time between the tuning cycle and that part of the data affected by fuel exhaustion - from about 8 a.m. through 1:30 p.m. This data was imported into Excel to run the statistics. Here are the results:
Maximum temperature: 229ºF
Minimum temperature: 219ºF
Average temperature: 224ºF
Standard deviation: 1.65ºF
The data show a slight improvement in the temperature regulation. Whether you want to go to the trouble of fiddling with this tuning procedure will be determined more by your desire to optimize performance than any real need to do so. Clearly, the advantages are minor - the manufacturer has done a good job of tuning the system right out of the box.
This test was done on a warm summer day. It is possible that if the test were conducted when the outside air temperature was very low, you might improve the temperature regulation more. Or perhaps not. One take-away from this experiment is that the controller isn't overly sensitive to changes in its operating parameters. This is a good thing because it indicates that it should perform well under a wide variety of conditions.
Auber has recently introduced two lithium-ion battery packs that can power up the entire controller package if AC power is not available. The smaller unit stores 3000mAH and the larger one stores 6800mAH. The main port provides 12.6VDC to power your controller and its fan. Each unit also has a USB port that outputs 5VDC to charge a phone or other device that charges via a USB port. See the links below for purchase information.