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Can an outdoor (alcohol) thermometer be destroyed irreparably ...

... after lying directly in the sun too long?

It's stuck at 43 °C / 104 °F:

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If yes, why (in terms of physics and/or construction)?

PS: Found no better Device than Safety. But it's safer to not go outside if it's 43 °C / 104 °F anyway. ;)

UPDATE

Neither the "overnight freezer" nor the "directly in the sun for a day" method mentioned in comments changed anything on the display. Running out of ideas atm.

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Hi Geri,

That is certainly an interesting situation! Assuming the glass isn't broken, I would assume it's not destroyed, but I'm not clear on how to get it back to its working state.

Under normal conditions, the bottom of the thermometer is filled with liquid, whether that's alcohol or mercury. There's a reservoir there that holds enough to fill the thermometer from top to bottom at its maximum expansion / highest temperature reading. Somehow yours has gotten the liquid displaced from the bottom so now as it expands it's expanding down instead of up.

I'm not at all sure how to get the liquid back down into the reservoir; if you can manage that it should go back to working correctly. I assume it got into its current state by sitting in the sun and getting too hot; perhaps the opposite will help, e.g., putting it in the freezer overnight? Or else maybe try using a heat gun at the top of the thermometer to try and expand that end and drive the liquid back to the other end?

I don't know, but I'm dying to find out how this all turns out!

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댓글 1개:

I remember having heard or read once in the past that it's even more sophisticated with medical mercury thermometers. The mercury expands from the reservoir into the tube and at a certain point the mercury column is cut off from the reservoir and expands further on its own. But it's not mercury in my case anyway.

And you're right. Looking at it closer now I see that the reservoir is totally empty and there's a gap until –38 °C / –36 °F (didn't realize that before). AFAIR I tried the freezer already (weeks ago) but not that long. Will do that now. Thx for the hint.

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Hi @starhack

Variation on the shaking method, is to grasp the thermometer firmly round about the middle of the thermometer and with the bulb end pointing outwards, raise your arm to just below the horizontal position.

Then swing your arm down quickly and when the thermometer is pointing straight down, stop. Do this several times.

Make sure that there's clearance so that you don't hit anything with the thermometer and also don't let go ;-)

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@jayeff perfect instructions :-)

Anyhow, how have your temps been? Mine is currently at 98° F or 32° C but it's not even 10a yet. @starhack how is your neck of the woods? You all cooling down somewhat?

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I see. You're counting on centrifugal force (and inertia). For the former, I think, it would be even more effective tying it to a string and spinning it standing on a chair or even a ladder. Will try both.

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@oldturkey03

It's winter here so it is cold at least for here it is.

Min temps are 6°C to 9°C and max is 16°C to 18°C

It's a wet start to winter (wettest June for 30 years) and windy as well so the wind chill factor makes the "feels like" temps about 3°C cooler than the actual.

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@starhack

Not sure about spinning as you don't want any liquid to go head back up to the top of the thermometer, although centrifugal force should keep it at one end, I suppose

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@jayeff I do hope you guys get the rain/moisture that you all need for the next summer. I know it can get brutally hot in your area as well

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Check for bubbles in the bulb from "cooking" the liquid, in the bulb of the thermometer. There is also a very sophisticated explanation for it. It is called Contact angle hysteresis. That is where the liquid/glass/vapor interface experiences total resistance to movement. Interesting reading about that on here

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댓글 9개:

Ethanol has a boiling point of ~78 °C / ~173 °F: https://en.wikipedia.org/wiki/Ethanol. You mean it got that hot inside? And the bulb / the reservoir is completely empty; see Jerry Wheeler's answer and my comment to it.

And for the records, and future readers: https://en.wikipedia.org/wiki/Contact_an... ... But (mathematical) faint-hearted beware: Sophisticated equations with a funny looking character (ϴ – like the extraterrestrial spaceship of the good[!] aliens in "Independence Day: Resurgence") ahead! :D

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BUT, your boiling bubbles brought me to another idea: The forecast for tomorrow is up to 34 °C / 93 °F here and if the "overnight freezer" is unsuccessful I'm going to put it in the sun in an upright position and hopefully all the steam below the alcohol column bubbles up to the upper end.

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@starhack That might just release this resistance. I would not have been surprised if it actually did get as hot as that. If the alcohol is in a vacuum, then the boiling point is lower. I am not sure if it is but worthwhile to consider What is with the 34° C? Cool front? I am still at 43° C. This is what must be meant by oppressive heat. My power company is going to love me this month $$$

Stay safe and drink plenty of fluids. Stay hydrated and make sure your animals have plenty of shade and fresh water.

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@oldturkey03 Re your 43° C: If your nick refers to your home country you're quite a distance closer to the equator than I'm here in Austria. And we still have snow and ice in some regions of the Alps (: though I'm not living in the mountains but not far from Vienna).

I'm also not sure about the content of the "empty" space under normal conditions. But if it'd be a vacuum wouldn't this suck out the fluid from the reservoir to the top immediately? I guess it's vaporised alcohol instead.

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@starhack No, it does not :-) but it's on my Abpout page. Anyhow, yes I am definitely closer to the equator. About 2,000 km closer since you are about 5,300 km away :-)

Beautiful Country and good food :-) Not quite like my Tex_Mex stuff. It is hot for all of you folks in Europe right now and we have to come up with better idea for the future.

¯\_(ツ)_/¯ possibly yes to the vacuum but stranger things have happened. I do hope you get it resolved and keep us informed about what is going on with it.

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Try shaking it down as you would a mouth thermometer.

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I tried that as soon as I realized the "damage". Unfortunately to no avail. And I didn't want to shake it harder to avoid breaking the thin glass tube and its even thinner upper end.

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You have a bubble of air below the column of alcohol. You may have to start by putting the thermometer in the deep freezer in a vertical position or get some freeze spray to lower the column enough to get the air bubble on top. Try going through cycles of cooling and warming the thermometer and try to moving the bubble to the top always keeping the thermometer in a vertical position. If You manage to get most of the bubble towards the top then try warming the thermometer with a hair dryer. You should wear safety glasses when you do the next steps incase the thermometer ruptures. Position the thermometer so it is vertical. Using a hair dryer slowly heat the very bottom of the thermometer forcing bubbles to the very top. Then slowly let the thermometer cool and as the alcohol starts to drop it should stay in one solid column. Good luck.

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