Just had a 4hr 40min power outage.
Powered the wood stove fan and fridge with batteries.
About 4.5 hours into it, fridge went into defrost cycle, consuming much energy.
Just as I turned off the battery supply, mains came back.
My Frigidaire late model side by side has no obvious, or non-obvious way to defeat the defrost.
The inter webs don't have much.
Maybe a wiring mod.
More research is required.
Thoughts?
edit: I used the below to alarm me when the freezer got to 1 degree. (I wasn't opening the door).
edit2: When plugged the fridge back into mains, it went into refrigeration mode, ie, no defrost. So maybe I'd be good for another 4 hours. Not good for a full night's sleep, lol,.
Chose not to power or open them for the first 6 hours of the outage. My fridge stays a safe temp for 24 hours without power if I don't open it.
Yes. That's sort of what I did. It got to 23F very quick before I plugged it into the battery. Side by Side or my model may be less efficient. I did open the door to look at the controls though. :). Still don't know if it could go to 6 hours without going over 32F.
I should say that while I have the freezer section fairly full, I turned off the ice maker, so there's no ice in the bin.
In older fridges you would just advance the defrost timer. Looking at the circuit board diagram for my current fridge everything is relay driving off the controller board. You could install a toggle switch for the power line leading into the warming element if you wanted to don't know if that will be detected by the controller if the element didn't show temperature rise since there are sensors all over the place.
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It's weird I couldn't find anything on the web, readily, about defeating defrost on a new appliance. I'm sure it's out there. Or, perhaps, a ZEN04 outlet to let it run for 3 hours or so, turn it off for 5 minutes and then on again for 3 hours. If that would actually do it.
What could that possibly mean 
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And here I thought I was alone in my responses... 
How do you know it is in a defrost cycle?
Modern electronic appliances have built in diagnostics and test modes accessible by pressing certain keys in a particular order. Maybe you can find the sequence for your unit and then there might a test mode to keep the fridge compressor/thermostat working but disable the defrost cycle. It sounds an odd use case so I'm not that hopeful, but maybe.
A simple power interrupt might reset the defrost timer logic so that defrost cycle won't run for x hours after power cycle. So just power cycle the fridge every x hours - 5 minutes....
You could always disassemble the fridge and put a switch in series with the defrost heating element(s) that you could open if this happens again. If you have wiring diagram might be fairly simple to locate the defrost power wire from the control board and insert switch there. If you want to "Hubitatize" it put a dry contact relay there....
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I have a dumb alarm tell me when freezer temp goes up.
It went off just now.
I pulled power, will wait 5 minutes, plug back in and see what happens.
If that works for, say 3.5 hours, I can set up the parameters in a ZEN04 auto on/auto off-no hub required.
Plug the fridge into the ZEN04 and then into the Bluetti.
Fingers crossed.
It's always something new in each outage.
Good luck. As mentioned earlier if its an old fashioned mechanical defrost timer switch then power cycle won't help (timer will continue from same point it left off at). But those fridges are becoming rare now.
I know. They're not made for manual defrosting, not that I recall ever doing that, lol. Pan isn't removable, I think. The emphasis is on kicking off a defrost cycle, not disabling it. I think I my model 5 pushes of the fresh food light (operated by the door) in 6 seconds puts it into defrost mode. But I'm not interested in putting it into defrost mode, lol.
Well, it's going down, so cooling not defrosting.
We'll see for how long.
Unfortunately my temp gauge does not do time-just date for the alarms.
And...my Zooz sensor doesn't work in the freezer. 
edit: You would think there'd some documentation around about how the defrost cycle is programmed, but I can't find anything, so far.
edit: I suppose I could write a rule as well to kick the fridge off when Watts reach a certain level, and then Auto On after 10 minutes. The LR ZEN04 will be plugged in to battery and theoretically the hub will be on backup power, but you know how that goes, lol.
I think most manufacturers keep the inner working proprietary so I doubt you can find much about the inner algorithms.
Current draw might be a way to do it. You need to know current draw for idle, compressor on, and heater(s) on, If they are different enough you can probably write a rule about it.
If the power cycle resets defrost timer = 0 works I'd just go with that. Just periodically power cycle fridge when main power is missing. I'm guessing it won't drop into defrost for a fixed period of time, I don't think they sense freezing conditions, they just turn on heaters every y hours for x minutes. Pretty dumb algorithm.
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Who knows though? It could monitor temperature history, door openings, etc.
Then there's my rule: nothing works as expected during a power outage, lol.
edit: Maybe there's a humidity sensor thrown in, lol.
Be aware that as frost accumulates on the evaporator coils and fins, as it always does, cooling efficiency goes down and the compressor runs for longer to compensate. Eventually, if enough frost accumulates, the compressor will run continuously (ask me how I know).
The defrost cycle is there for a reason.
Of course. See first post regarding conditions.
You may be missing the point. Look at the graph below. That step at about 550W is the defroster coming on. For all of 7 minutes. The rest is the compressor cycling on and off.
What matters is the area under the curve. Clearly in this case the compressor overall consumes the most energy, in comparison the defrost cycle energy consumption is not significant (assuming your battery backup is able to keep up with its peak power demand).
The point is - if the compressor has to run longer because of frost, that might, over time, negate any efforts to save energy by cutting the defrost cycle. How much time? Depends on your unit, ambient humidity, etc.
Hopefully any potential outage won’t last too long.
Also that graph might be of old tech. 150 watts running, 500 watts max on defrost. My two year old model is a lot less.
It’s all about stretching out the battery.
What's wrong with "old tech" ? That's a 1995 GE
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Nothing, except when powered by a lame ■■■ battery.
