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rjwut t1_iy3zz7n wrote

Lower temperatures slightly increase the battery's internal resistance, pushing it just past the low power alarm threshold.

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EvilRedRobot t1_iy44v1l wrote

Thank you. This mystery has haunted me for years! To solve it, I will now place a small candle on the floor under the alarm every night so I can rest with peace of mind.

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Nimelennar t1_iy4js68 wrote

That's a waste of energy.

Me, I'm going to pack around it with some insulation so that it isn't exposed to the cold air of the house.

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Kat121 t1_iy4gusw wrote

Transistor gain absolutely decreases with temperature.

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Dopeydcare1 t1_iy58gv8 wrote

Yup. I figured this out when I dropped a phone in the pool long ago and I dried it out, it worked, but every single time the temp dropped below 45 (SoCal, so not too often) when I was outside, my phone batter would drop from whatever it’s at to 1%

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THE_GR8_MIKE t1_iy58aqu wrote

How cold do you let your place get at night?

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rjwut t1_iy6s5ai wrote

It doesn't have to get very cold; only slightly colder than during the day.

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rjwut t1_iy54fpx wrote

Corrected a mistake in my original comment: I accidentally wrote that resistance was decreased instead of increased.

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thephantom1492 t1_iy5woov wrote

DUH! of course! . . . Why didn't I tought about that before?

And it explain also why in winter too, we set the heating at 18°C at night and 21°C during the day, but the ceiling itself being the attic is most likelly quite colder (the insulation is trash, I need to redo it, maybe this spring?)

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