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This is perhaps a weird question, so here is some background, explaining the motivation:

For the past 20 years we have always owned dual-fuel ranges: (electric oven with a gas cooktop). The main reason we buy dual-fuel is that during a power outage (which we get frequently -- five in the last year, three of which lasted 4 days or longer) we can still light the gas burners with a match and cook. (Of course, we can't bake in the oven.)

Anyway our most recent dual-fuel oven (a KitchenAid KFDD500ESS) came with a disappointing and surprising new "feature": when the power goes out, the gas shuts off! Apparently this is a "safety feature" that other folks have noticed as well (the linked thread is about a different oven that has the same issue).

I would like to find some way to keep the gas valve open when the power goes out. Obviously the optimal solution would be to purchase a whole-house battery backup system but that would run me up to $14,000, so is not practical. I'm also not interested in a generator. Instead I'm considering spending a few hundred dollars on a portable power station. The problem with that plan is that they only supply 110V, and the oven plugs into a 220V outlet.

Just to be clear: I do not intend to actually use the oven during a power outage. I realize that trying to bake something at 350° would surely draw more power than an affordable portable power station can supply. I just want enough power to keep the oven on "standby" mode: basically, keep the clock and the control panel turned on and the solenoid (or whatever it is) holding the gas valve in the open position so that we can use our gas burners and make soup, scrambled eggs, stir-fries, pasta, etc.

The question is: how do I connect a 220V oven plug into a 110V power station?

The only solution I have come up with so far is to buy a 110V-to-220V step-up transformer, plug that into the power station, then try to find an adapter that will let me connect the oven plug into the transformer. My questions:

  • Would this even work?
  • Would this be safe?
  • Is there a simpler (or better) way to solve my problem?

Other (somewhat disorganized) thoughts: what would happen if I plugged the range into a portable 110V power supply (using an appropriate adapter) without stepping up the voltage in between? Obviously it wouldn't be enough to run the oven (which, again, I have no intention of trying) but would the range controls turn on? Would I be at risk of damaging the range if I did this?

Again, just to clarify: suggestions to power the whole house with a generator, or to replace the oven with a different model, are appreciated but are not what I'm looking for. I just want a minimal solution that would allow me to keep the gas burners on my current oven working when the electricity goes out.

mweiss
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  • Comments have been moved to chat; please do not continue the discussion here. Before posting a comment below this one, please review the purposes of comments. Comments that do not request clarification or suggest improvements usually belong as an answer, on [meta], or in [chat]. Comments continuing discussion may be removed. – BMitch Jan 19 '24 at 13:55

6 Answers6

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You're probably wasting your time trying to make 240V.

While your particular oven happens to be dual-fuel, you can bet that all this oven control circuitry is also used in their all-gas ranges (which have a gas oven). Those appliances will be entirely 120V creatures with no 240V available. So it only makes sense that the control module is either 120V or dual voltage.

“how can it get 120V?" You might ask. "I have seen the AC power plug and it is only 3 wires -the third must be ground because this is the 21st century for Pete's sake!" Unfortunately for safety, that slanted-pin "crows foot" plug actually does go back to before 1954 when grounding started to come in. The NEMA 10 plug has no ground and that is neutral.

So you would be wise to look closely at the schematic and see for yourself how it is powered.

Harper - Reinstate Monica
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Determine if you can get what you want with 120V

It's likely the oven has a 120V light bulb in it, therefore likely range has a neutral conductor and so maybe the electronics use 120V too. You can look at the wiring diagram and/or figure out with a meter which hot leg is used for 120V, disconnect the other one, and see if the gas functions work. If they do, you can figure out a safe way to wire up a 120V power station feed.

Wire up a 120V backup feed.

If you determine that 120V will work, you can put together a junction box with a standard 120V 15A plug and a socket that suits your oven. There is nothing wrong with plugging the oven into a correct 50A socket (or whatever it needs) but that is only capable of delivering 15A. The main problem I think will be getting access to the plug. Are you going to move the oven away from the wall to do this? And place the power station on the counter next to the oven? And will the cord reach there?

240V possible

If the range insists on 240V just for the electronics, sure it is possible to run the power station through a step-up transformer but you'll be getting fast diminishing returns and your kitchen set-up will look more like a science experiment. Look into buying a European version of the power station, then build a plug converter as described above.

[Adding this] I see now there are some battery power stations in the US market with dual voltage output. Adding this just for completeness. Not a recommendation, they are insanely expensive. For the price of one you could buy a nice portable generator, install an inlet and interlock, and have enough left to replace your range with an all gas one.

Keep it DC?

Who knows, if you look at the wiring diagram .... maybe the electronics use 5V or 12V? You never know. Then a much better hack would be to get inside the range, and wire in a suitable plug (USB or whatever) on the back of the range and use THAT to power the electronics from a portable power pack (phone charger) or similar during an outage. Yes you'll void the warranty and if you screw up you could fry the board but this would be way more efficient and cheaper than your plan, and more fun, and you would not have to move your range to plug it in.

jay613
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    Please note that modifying the electronics inside your oven will probably void your insurance if the oven ever catches fire, even if it has nothing to do with the electronics you modified. You will not be paid a cent for your house that burned down. – user253751 Jan 18 '24 at 07:07
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    @user253751 can you offer any substantition for that comment from any actual insurance policy terms or from law in any state or country? – jay613 Jan 18 '24 at 09:12
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Depending on how handy you are, you may be able to replace the valve. If the valve is truly just the safety valve, you could replace it with a straight pipe and ignore it, but if does double duty as the valve supplying the jets (which I can't think of any way this would work, since each knob should be a valve, unless each knob valve has the feature built in) then you would have to replace it with a valve you could manually turn on or off.

Another answer suggested that the control and valve may be dc; there's a good possibility that the valve itself is dc even if the control circuitry doesn't give you a way to power the board with dc. So you could probably cut the leads from the valve and wire them to a separate switch and dc adapter powered off a battery backup. I've done that before with appliances where the circuit board has gone out and I don't want to replace it. It may be that it screws with a control board if you leave it cut (eg, the control circuitry may start throwing a fault about bad gas valve and not let you even use the electric oven), so you may need to wire the switch so that when flipped one way, the control board controls the valve, and the wall-wart controls it when flipped the other way. (And technically, if the control circuitry doesn't care if the valve is there or not, you don't technically need the switch, you could wire direct to the adapter; the switch in that case is just if you wanted to theoretically keep a safety feature of being able to turn off the gas for some reason, like leaving the kids home alone or something.)

Dan Lopez
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Good morning! If I had this question (and may in the near future) I would go to my panel. Find oven breaker and turn it off. Remove panel cover. (If this is not your jam, stop here.) Locate oven breaker that you just shut off and remove either the black wire or the red wire. Turn breaker on and go see if your gas lights. If no then replace and repeat with other wire. This will tell you which 120 leg is powering the controls of the range. * Once you know which leg, (red or black) powers the control circuits any desired off book intervention can occur at the panel. No moving range. No altering of range. If the power goes out, shut off that oven breaker(to protect the helpful lineman) and power up that wire that you have determined to be the line to the controls of the range. How you do that should be in place only when the breaker is in the off position. A 120v hot line from your temporary power source to that chosen line and the neutral side to the white/ground bar of the panel. Again, first visit here. Just suggesting the point of intervention might easier be at the panel, if it were me.

*Chances are the same range comes in an all gas version which would have a single 120v plug. It's unlikely there would be two wildly different control systems on two models of the same brand.

Mick
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    Welcome to [diy.se], please take the [tour]. There's some merit to what you're suggesting, however, the OPs power supply provides electricity though regular NEMA 5-15/20 receptacles. How would you suggest getting that power into the panel in a code-compliant and safe manner? You really can't run an extension cord into/out of your breaker panel... Also, an [edit] to add some formatting and remove the "I'm new" info would be useful. We can tell you're new, you've got 1 rep point. ;) – FreeMan Jan 18 '24 at 16:14
  • Thank you for your thoughts. I would not presume to suggest how when I have no knowledge of the OP and expertise. Merely attempting a redirect from taking the stove apart or other code compliant suggestions. If I am in error, please forgive me. – Mick Jan 18 '24 at 17:04
  • No apology necessary, just take a look at how to write a good answer for info on what's expected here. – FreeMan Jan 18 '24 at 17:10
  • I will muse on that "how". Thanks. – Mick Jan 18 '24 at 19:26
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The "dual fuel" term is confusing. I've mostly seen it used in generators, where you can use either gasoline or propane to run it. In other words, there's two types of actual fuel. Ranges, however, use the term very differently

Dual fuel stoves and ovens use both gas and electricity as fuel sources, which maximizes both fuel types to let you to cook and bake more efficiently.

What this means is you have gas burners and an electric stove. The 240v plug is so you can power the electric oven. While the electronic components might be 120v, you're going to be hard pressed to adapt this in a way that will be safe. The other consideration is that your range is probably also needing 30A or more. Even if you adapted a 120v device, you run the risk of someone forgetting it's in a battery and trying to use the electric oven.

What I would suggest is selling the dual fuel and buying a pure gas range. I have two of them, and both only needed a 15A/120V connection. Gas ovens will do anything an electric oven does.

Machavity
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    There is no evidence that anyone here is confused by the usage of "dual fuel" to describe a range that has a gas cooktop and an electric oven. The OP certainly isn't, as they spelled out the situation perfectly clearly in their question. – nobody Jan 19 '24 at 00:12
  • Furthermore, the suggestion to switch to a pure gas range is not helpful. Why would a brand new pure gas range not also have an electric gas control valve that would need AC power during an outage? – nobody Jan 19 '24 at 00:15
  • @nobody He wants to run the stove off a battery pack that provides 120v. Virtually all gas ovens will run within whatever amperage the battery provides. That renders the issue moot as far as any valves go. – Machavity Jan 19 '24 at 01:03
-2

This is perhaps a weird question

not at all. This sort of things happens all the time when it gets cold or power goes out and things people unknowingly bought in to don't work and they either didn't recognize the probability of it happening or were in denial. Same thing with all the electric cars in chicago right now that are dead because of the cold.

The question is: how do I connect a 220V oven plug into a 110V power station?

you simply need a 110VAC to 220-240VAC transformer.

https://www.walmart.com/ip/5000W-Voltage-Converter-Transformer-110V-to-220V-Step-Up-Down-AC-Adapter/635425939

Is there a simpler (or better) way to solve my problem?

yes, but to tell you the better way would mean getting political.

ron
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    This won't work. While the transformer would indeed provide 240v, it would only provide a single phase 240v (i.e. what you would find in Europe and elsewhere). North America is on the 240v split phase system, so you need two 120v legs, not a single 240v one. This transformer would damage the stove in question. – Machavity Jan 18 '24 at 17:26
  • how would 240v single phase as opposed to split phase (+120v/-120v) damage something intended for 240v on two AC connections? – ron Jan 18 '24 at 19:43
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    Because not everything in the range takes 240v. If you look at a range plug (often a NEMA 14-50R) you'll note that there's 4 prongs: two hots, a ground and a neutral. Dryers and ranges often use 120v for the electronics (in a country where all the other stuff uses 120v), and only use 240v for the heating elements. Use 240v there and you'll likely fry the boards. See this answer for how split phase works – Machavity Jan 18 '24 at 19:49
  • i did not say connect 240v to neutral. – ron Jan 18 '24 at 20:11
  • Did you say that explicitly? No. But you linked to a transformer that does single phase 240v hot, neutral and ground (which, again, is standard in Europe and elsewhere). That type of transformer is trivial to find (any travel converter will do that). I have never seen a step-up transformer that will take a single-phase 120v and convert it to a two-phase 240. – Machavity Jan 19 '24 at 14:19
  • If you understand electrics it's easy enough to wire up a transformer to take 120V input and produce US style 240V output. The reason you don't see it as a consumer product is that it has very limited utility. Most loads that require US style 240V will overload most 120V supplies. – Peter Green Jan 19 '24 at 21:17