Converting my 220V to 110V

Discussion in 'Fridge/Freezer Builds' started by iowa josh83, Oct 6, 2015.

  1. iowa josh83

    iowa josh83 Smoke Blower

    I'm tired of not being able to take my smoker places because they do not have 220V available. Like any competition. So I want to convert it to run on 110V.

    Here's my setup today: Old GE fridge, running an old GE oven broiler element (220V) controlled by the oven's electronic control board. I know the control board runs on 110V already because I had to wire a neutral for it to come on.

    Here are my thoughts, the current element is huge! Overkill for the smoker IMO. From what I can tell its 2500-3000 watts. When I do the math using 120V that is potentially 27 amps, so I'm in the same boat because most people do not have 30A circuits conveniently located for a smoker. 

    So I went looking for a smaller element and found a heck of a deal on some 900w elements that I think might fit the bill.

    Here's my thoughts and where I need your help. Right now I have 2 "hots" that run to the current 220V element. If I convert one of those to a neutral and use the other switched hot from the control board I should be good right? Obviously I'm not an electrician but I know my way around a tool box.

    Any thoughts or discussion would be appreciated.


  2. dward51

    dward51 Master of the Pit OTBS Member

    Running a 220v rated element will de-rate it to 25% of the original wattage rating if my memory serves me correctly.  It's been a while, but plug the numbers into ohms law and you will get the results.  So the short answer is yes, you can rewire a 220v element as a 110v element, but the cost is in the wattage output (resistance remains the same, voltage is halved).  It does not just draw twice the amperage like you think it would so the 27 amp figure is not valid.

    Assuming your 27amp draw figure was twice what it would be at 220v, that gives us 13.5 amps at 220v.  So using ohms law the resistance of the element is about 16.3 ohms.  So plugging that number in with the reduced voltage of 110v gives us 6.75 amps for that element at 110v or a total potential output of 742.5 watts (or 1/4 the original wattage at 220v).

    It will work, but it will be like having a 742.5 watt element.  The good news is it will never burn out run like that.

    Go buy a Brinkmann 1,500 watt, 110v element online for $25 or $30 and be ahead of the game.
    Last edited: Oct 6, 2015
  3. iowa josh83

    iowa josh83 Smoke Blower

    I forgot to mention the 900w element is a 120v element & it was only $6.34. Way cheaper than the Brinkman element.

    My figures were all based on the wattage of the element divided by the voltage. Is this not the way to figure amps?

    Thanks for the input!
  4. madman mike

    madman mike Smoking Fanatic

    Dward i correct, if using a 220v element connected to only 110v then the watts are only 1/4 of the 220v rating. 2000w @ 220v is only 500w when connected to 110v.

    you are correct on how to calculate the amps, but you have to use the decreased watts/110 for the actual amps when running the 220v element on only 110v

    3000w x .25 = 750w / 110v = 6.82amp
    Last edited: Oct 7, 2015
  5. radioguy

    radioguy Smoking Fanatic

    Dward is correct. Rated wattage is ONLY at the specified voltage. The load (ohms) is constant. How big is your box? Can 700w heat it? Otherwise get a 110v version that suits your needs. You also can run two lower wattage 110v elements. You'll have to plug it in to 2 different 110v circuits.

  6. iowa josh83

    iowa josh83 Smoke Blower

    Again, the element that I plan to replace the 3000w element with is a 900W, 110V element.

    I think the 900W element will heat the smoker, If it won't I bought 2 of them and I'm confident that 1800W will heat it. But then I'll have trouble with too many amps on a 15A circuit.
  7. smokin phil

    smokin phil Smoking Fanatic

    Last edited: Sep 17, 2016
  8. jckdanls 07

    jckdanls 07 Master of the Pit Group Lead OTBS Member

    sounds like your pretty set on using the 900w element... so give it a try ... If your adamant on using the same controller as well.. then try it... if it doesn't work as you wish.. then I suggest the 1500w as well (as suggested above)... If it were me.. I would just go with the 1500w and be done with it (which I did in a MES 30, just to experiment) ...
  9. If the element is really rated for 900W at 110V, then you only need to determine whether 900W is enough. If it isn't, then you could add a 400W or 500W element in parallel on the controller, or you could add the other 900W element on another cord powered by another circuit from another circuit breaker. You wouldn't need to control it. You could leave one element always on, because you know that 900W isn't enough, and let the controller supplement by controlling the other element. It the controller fails to keep the temp low enough, you can unplug the always-on element.
  10. dward51

    dward51 Master of the Pit OTBS Member

    In the original post it was indicated the smoker was a converted "old GE fridge".   Depending on how well it is insulated, 900watts may or may not be enough.  Most of the old fridge conversions I've seen have a lot of volume.  The more volume, the more work the element will be doing to get, and keep the desired temp.  Heating air alone is no big deal, but toss in a load of meat and you change the game considerably.

    Exactly what do you plan on smoking in the fridge with the 900watt element?

    You used the language "like any competition" in the original post.  If you are planning on using that smoker on 110v with the 900watt element in a competition, I am concerned that it may be too small.  In a competition, you generally are smoking more than one of what you are turning in, and sometimes you need the ability to crank up the heat to get past a stall or make up for lost time as a deadline approaches.  900 watts will not leave a whole lot of flexibility, especially if it is barely enough to heat the interior of the fridge for competition smoking.

    Now on the other hand if you are talking about snack sticks & sausage, then that is something totally different and it may be adequate.
  11. zach5483

    zach5483 Fire Starter

    Would love to see pictures of your rig set up, and of the elements you bought.

Share This Page