Building a Smoker - How to Add a Thermostat?

[wa0auu]

That is not a hard job, start by buying a thermostat to control an electric oven.  Place the bulb in the oven and set the oven to the temp you want the  thermostat  to OPEN, turn off.  Say you want to keep the heat at 225, then set your oven to 225 and put the new thermostat bulb in it and when it says your oven is at 225 then turn the shaft of the new thermostat till it  OPENS.  Now your new thermostat is set to 225 F.  TO wire it in, first >>>>>>> be SURE ALL POWER HAS BEEN REMOVED !  If you want the new thermostat to control the heater in the smoker,   the black ( hot) wire from the line cord goes to one contact of the new thermostat, the other contact on the thermostat goes to one side of the heating element.  The other side of the heating element goes to the white wire on the power cord.  BE SURE to put the green wire to ground

 

[willi-b]

I like your set up and wonder if you'd take the time to share details of your entire smoker setup - including type of heat and how you wired your unit.  I am presently converting a commercial well insulated fridge into a cooker/smoker and want to add controls to it similar to your setup.  I'm trying to decide between LP and electric.  I'm leaning electric due to simplicity and the fact that my box is super insulated.  Here's a few pics of my box. 

Smoker Conversion Box.JPG

• willi-b
• Jul 9, 2016

Smoker Conversion Box-2.JPG

• willi-b
• Jul 9, 2016

I had the refrigerant evacuated and the top where the compressor and coils were will now house the stack and controls.  I did a heat test on the insulation sandwiched in between the outside and inside stainless jackets and it does fine up to 350 degrees F.  I don't plan on cooking at temps higher than that anyway and will most likely be at 300 F max. for larger cuts like briskets and hams.  The original rubber and magnet door seal will be replaced by either rope gasket or metallic oven door type gaskets. 

The box inside dimensions are: 60"T x 24"W x 27"D or approximately 20 Sq. ft of cooking space.  I'm unsure of the power of heating element I need as I read conflicting accounts of those who have electric smokers.  Seems to me that if a Bradley or MES uses a 500 watt element for their smokers that are about less than half the size of my box - and the fact that my box is about 100% thicker and better insulated than those boxes, I could easily get away with a 1500 watt element and keep this at 120v.  However, I am trying to find a way to calculate the heating requirement of my box.  I'm also researching doing a dual element design where the large element will be used for cooking and a smaller one for holding temp after cook is done.  However, do you think the large element can be modulated to a lower wattage with the PID controller after cooking is complete to a hold temp so a second element isn't needed?  I also read that in these larger type vertical cookers, hot spots can develop which a convection fan will alleviate.  What's your thoughts on a convection fan that can be controlled by the PID controller to come on periodically to distribute the heat better throughout the entire box? 

Thanks in advance, Willi-B