Out of the box insert fan automation

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NoGoodAtScreenNames

Feeling the Heat
Sep 16, 2015
414
Massachusetts
Every now and then I see questions on measuring temps on inserts and automating the controls. I thought I’d throw out my setup after running it for a year.

I started with the standard Auber probe alarm which works well. After a couple years with that, I looked into something that would automate turning the fan on and off. My snap disk sensor on the stove is a little slow to respond at startup. I could have a roaring fire but the sensor is still cool. Then if the fire is smoldering from turning the air down too much or the fan being too high the fan would still be running.

I landed on buying an all in one PID controller from Auber.


This has a lot of cooking functions that I don’t use but I didn’t have to build my own device which was a selling point for me.

I measure the temp using a washer style probe jammed between the flue adapter and the stove collar. The insert fan plugs into the back and is in “always on” mode.

I use the controller in cooling mode. When the temp is above 400F it turns the fan on. If the temp drops below 360F it turns off and will turn on again when it climbs back up to 400F.

I like it a lot. I used to manually turn off the fan in the later stages to keep the noise down (even though my fan is pretty quiet). Now that happens automatically and I don’t have to remember to turn it back on during a reload.

I picked the temp setting based on observations for how the stove performed with the air shut down. At 400F I could always expect some good lazy secondaries and at 360F it would seem to change over to the no flame coaling stage. So it cycles between stealing some heat and dampening the flame and then giving a period of time to warm up from the coals, reignite and start the cycle over.

The same thing can happen in the early stage. If I’m too aggressive at turning the air down and the flame goes out, the fan will turn off, allowing the temps to increase which pulls more draft and can restart the flame. If the fan stayed on, it may have just sat and smoldered for much longer.

The controller also has an alarm setting if it gets too hot. I currently have it set to 600F. This is well below my over fire point but high enough that I can stay below it with normal operation. It goes off a few times a week, but it’s just a reminder to shut the air a little more or turn the fan up. I still use the original Auber alarm that I bought a few years before the controller as well. That measures stove top temp and is set as my real over fire alarm. I forget what that’s set at as it’s never gone off since I set this up.

So far it’s been working very well for me. You could custom build something from individual parts but the plug and play is fast and easy and is not too expensive compared to the standard digital monitor.
 
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EbS-P

Minister of Fire
Jan 19, 2019
1,253
SE North Carolina
Nice, I had thought about doing that as well. Auber makes some good products. I was going to use the one they made for green egg fans a few years back.
I like that a lot. It’s simple and ready to put into use.
Evan
 

NoGoodAtScreenNames

Feeling the Heat
Sep 16, 2015
414
Massachusetts
Nice, I had thought about doing that as well. Auber makes some good products. I was going to use the one they made for green egg fans a few years back.

Yeah, they have a lot of stuff that could be used off label for other purposes. A lot of the controllers seem geared towards sous vide cooking - which I had to look up to see what that was. Maybe some day in the off season I’ll use it in the kitchen.

The Auber customer service was good. They replied pretty quickly to a couple of questions I had to make sure I was buying the right thing. If I wanted to do something fancier, I’m sure they would have helped design it from their other stand alone components.

The only thing I thought I wanted at first that it won’t do is control the speed of the fan based on the temperature of the stove. Wasn’t sure if the fan would do well with a variable current through the plug and didn’t want to re-wire anything. In retrospect though that feature actually would have been more annoying than helpful. I like the on / off since I run the fan on the lowest setting unless the peak temp is higher than normal.