Cheap element controller

[wjordan52]

Many new electric smokers have a method of controlling the smoke chamber temperature, but those of us who want to build our own have to come up with a custom solution. I have seen a number of very nice looking electronic controllers on the Internet, but all are too 'rich' for my blood.

Being accustomed to not having enough money for the 'good' stuff, and not about to do without, I started looking outside the box. My first thought was to use a power tool speed control, as I see a number of folks do with much success. However most reviews I've read mention varying amounts of heat generated by these devices. Using my limited understanding of electronics I have to assume the heat comes from the resistor dissipating energy that would normally go to the tool. In my mind this translates to wasted energy, which has a negative effect on my power bill.

Then I thought about conventional stove top burners. They have a simple dial that sets the relative heat of the burner, but on my stove I've never noticed any appreciable amount of heat in the vicinity of the dial. After a little research I found that they work by using timed on/off cycles, therefore varying the percentage time power is applied to the element during each cycle. Basically it repeatedly turns the element on and off depending on the setting of the dial. When on, all the energy goes to the element. When off, no energy is used. I liked the idea.

The part used in a stove that I refer to is called an 'Infinite Switch', and is easy to find and fairly cheap. I was able to buy a switch rated for 120v and 15amps at my local appliance parts supplier for ~$35. They can be bought for less by ordering online, but I wasn't patient enough to wait for it to be shipped. I then dug around in my garage (not a safe undertaking by any means) and found an old surface mount 220v stove receptacle. By gutting the 'innards' I was able to mount the switch inside and attach the necessary 120v wiring. After adding a small hook to the back for hanging the controller and a couple of indicator lights I was ready to for a test.

I've used my homemade controller on 3 smokes so far, and during each the device kept the smoker temp very stable once I got it 'tuned' to the right setting. Not automatic of course, but for the price I find it a good substitute. I hope you will find this useful.

Here's a pic of the controller I built:

 

[i bleed blue]

Many new electric smokers have a method of controlling the smoke chamber temperature, but those of us who want to build our own have to come up with a custom solution. I have seen a number of very nice looking electronic controllers on the Internet, but all are too 'rich' for my blood.

Being accustomed to not having enough money for the 'good' stuff, and not about to do without, I started looking outside the box. My first thought was to use a power tool speed control, as I see a number of folks do with much success. However most reviews I've read mention varying amounts of heat generated by these devices. Using my limited understanding of electronics I have to assume the heat comes from the resistor dissipating energy that would normally go to the tool. In my mind this translates to wasted energy, which has a negative effect on my power bill.

Then I thought about conventional stove top burners. They have a simple dial that sets the relative heat of the burner, but on my stove I've never noticed any appreciable amount of heat in the vicinity of the dial. After a little research I found that they work by using timed on/off cycles, therefore varying the percentage time power is applied to the element during each cycle. Basically it repeatedly turns the element on and off depending on the setting of the dial. When on, all the energy goes to the element. When off, no energy is used. I liked the idea.

The part used in a stove that I refer to is called an 'Infinite Switch', and is easy to find and fairly cheap. I was able to buy a switch rated for 120v and 15amps at my local appliance parts supplier for ~$35. They can be bought for less by ordering online, but I wasn't patient enough to wait for it to be shipped. I then dug around in my garage (not a safe undertaking by any means) and found an old surface mount 220v stove receptacle. By gutting the 'innards' I was able to mount the switch inside and attach the necessary 120v wiring. After adding a small hook to the back for hanging the controller and a couple of indicator lights I was ready to for a test.

I've used my homemade controller on 3 smokes so far, and during each the device kept the smoker temp very stable once I got it 'tuned' to the right setting. Not automatic of course, but for the price I find it a good substitute. I hope you will find this useful.

Here's a pic of the controller I built:

I bought the "SE Stepless Speed Controller" from amazon for 18.50 +Shipping for my Gourmet Electric ECB a few weeks abo and have had amazing results. Now that I have my Maverick ET-73, I was abale to do some test "burns" to verify where I can Tick the dial positions for the most accurate temperature. I can get it from 0-267 degrees with the water pan filled in my unit. I also replaced the lava rocks with ceramic diamond briquettes.

 

[wjordan52]

Sounds like you've also found a good solution, and good to hear it's working so well. The unit you have is the very one I was thinking seriously about buying (it certainly is a lot nicer looking than mine). If you don't mind me asking how hot does this unit get when you use it? I'm curious to know if my thoughts were anywhere near right.

Adding mass is also a good way to stabilize temps, as you've probably seen in your ECB. I'm a scrounger and often check the metal bin at the local recycle center. A little while back I found a 35# barbell weight that looks to be all cast iron. I'm going to hit it hard w/ the torch to get rid of the paint on it's labeling (and anything else that might be embedded in it) and throw it in the bottom of my smoker, right above the element. It just happens to be 14" in diameter (my smoker is 16") so my hope is it will act as a diffuser as well as heat mass.

By the way, my original post was meant to describe a cheap, homemade solution that'll do until I can afford something better. It was not intended to imply that what I scratched together was in any better than quality, purpose built devices. Actually I'm saving for a good PID myself.

 

[i bleed blue]

the back gets pretty warm, about 175. Roughly the temp of the back of my iMac. so I have it hanging on a hook. I am a server engineer & project manager, but cant solder to save my life so after some dilligent searching I stumbled upon that unit and a similar unit at harbor Freight

 

[wjordan52]

Well, mine gets about the same I would guess. I can still keep my hand on it but it definitely puts off a little heat. Not sure it's a problem, and I attribute much of it to being in a sealed case. A new one w/ vents is in my plans.

 

[woodcutter]

I am using a 220 (double element) stove ring with a standard stove switch. I put a 10" cast iron frying pan on the element and fill with wood pieces. My switch can control the temperature pretty well until the wood pieces start burning/smoking and than the temp rises higher than I want.  Are there any options with a thermal couple or way to better control the switch?

 

[wjordan52]

Woodcutter... There are others on here who can give you a much more educated answer with regards to electronics/devices to control an electric element. From what you say however I don't think your stove switch is the problem. If your "switch can control the temperature pretty well" then that's about all you need.

It sounds to me that you need to control the wood pieces; they should smolder and NOT burn. The flames are going to run the heat up and there's no controller I know of that can help that. Not knowing any more about your smoker or setup, I'd suggest raising the cast iron frying pan above the element a little, or perhaps close down the draft (if it's adjustable) to starve the wood of air.

 

[woodcutter]

I've been thinking about what you said regarding controlling the wood and raising the pan and that is starting to make sense to me. When the wood is smoking it will burst into flames when I open the door and starve for oxygen again when I close the door. I think I will make some sort trivet or something to raise the pan. Thanks for your suggestion! 

 

[wjordan52]

I think you're on the right track. Also if the wood is hot
enough to flame up it may be putting off more smoke
than you need. Let us know how it works out.

 

[wjordan52]

Oops... sorry for the double post.

 

[woodcutter]

I smoked 2 butts on the 4th and raised the pan 1/4". It helped stabilize the temperature but I need to raise it a little higher yet. I think I will find the sweet spot. Then I will weld a trivet together at the right height. Butts turned out great!

 

[wjordan52]

Great! Thanks for the update.

 

[stovebolt]

   You should consider getting one of the AMNPS pellet smoke generators. That way your smoke will not be controlled by your heat setting. Look into it. It's a great gadget.

Chuck

 

[wjordan52]

X2. Those things are fantastic.

 

[i bleed blue]

I have considered that, however, in my Electric ECB...where do I put it? On the heatin element may cause a malfunction.

 

[wjordan52]

I built a seperate box w/ a short aluminum chimney for mine. Once lit I but the box under the smoker near the draft intake, and it works like a charm.

I've never had an ECB but I know a bunch of folks on here either have one or had one in the past. Probably the best thing to do is start a new thread asking about using an AMNS with an ECB. You'll probably get a lot of good ideas.