fixing max/min thermometers

[Tina]

Hi
I have 7 max/min thermometers. One works! I desperately need two. I got a second one the other day and it got dropped in class and of course doesn't work anymore!!!!

I have worked out how to use magnets to move the blue bits up and down and get them unstuck from the mercury.

What about air bubbles? The box says to put them above a radiator. What do people use as their radiators? does it actually work? I haven't had much luck yet. Tried a retort stand above a hotplate!

I also have a few where the mercury is not at the same level on both sides. I am assuming there is some mercury bits broken/missing from one side but cant see it.

Any ideas gratefully accepted.
Tina

[Ocker]

You could use a hair dryer to heat till gap in mercury goes up into small resevoir at end of tube then allow to cool and there should not be any gaps in column.
I don't understand what you mean by columns not equal if either side does not equal temp at that time you could always put note on thermometer of correction factor.
i.e. min temp reads 1 degree high or low whatever

[RosalieM]

We have a few if you want to borrow them, Tina. But some of ours have air bubbles in the mercury too. I have used a hair drier to heat them and put them in the freezer to cool them in attempts to reunite the mercury but it hasn't really worked. I might have to try the magnet to get the mercury that's above the markers back down... I read somewhere that they should always be stored vertically so I had the maintenance people put up some nails to hang them all on and there haven't been any more casualties since then.

[Rowyrow]

Maybe a hair dryer as a substitute for a radiator? I remember having trouble with these where i use to work in an animal lab. the insrtuctions to fix thme worked for a while but there is a point when they are just stuffed, eventually we gave up and bought digital ones, they give you humidity aswell as max and min temp.

[Tina]

Thanks everyone. I will go and try the hairdryer trick, though those new digital ones sound so tempting...

i don't need them now till next wednesday or so, Rosalie, so I will try fixing these first. Thank you so much for the offer. I really appreciate it.

Tina

[matchstick]

hello
If it is mercury in the thermometers then you shouldnt have them at all!!!!!!!! They should have been disposed of years ago.
M

[Ocker]

Mercury Thermometers are OK hanging on the wall,It's only when they get broken they present a problem.
You'll find a stack in hospitallity as candy thermometers and I have a tray of 350 degree C ones that I only lend to teachers with dire threats about care!

[RosalieM]

We only bought ours last year. I don't see why it's a problem to have mercury max/min thermometers. The kids generally don't even touch them so are unlikely to break them. They are encased in plastic and can't roll. Can you even get non-mercury max/min thermometers?

[Labbie]

Yes you can get Non mercury max/min thermometers. We got ours from Q-stores. last year.

[smiley]

Ummm,

Can't you shake the mercury down like we used to do with the old clinical thermometers? Just don't let go

[RosalieM]

I tried that, too, Smiley. It didn't seem to work :( Well, not for me, anyway. Someone else might have better luck with it!

[Tina]

Thank you, thank you, thank you!!!!

Thanks to your hair dryer tip and an hour of my time, I now have 3 working max/min thermometers. The hair dryer at its max temp setting got the air bubbles moving up, though sometimes the mercury and the marker too. Had to be careful the mercury didn't disappear into the top bulb.

The other four thermometers are still being difficult. They all have mercury somewhere in the top of the bulb (I assume) and I can't get it back down, so the two sides of mercury read different temperatures (up to 10 degrees of difference!). I better check how much digital thermometers cost!

I had to share my little triumph with you. After an hour of grim determination to win against these little blighters, I danced out of my little room with my three working thermometers and expected the teacher who wanted them so desperately to be at least a little bit happy about it too. All I got was a: "hmm? Can I have ...(blah blah blah) for period 4 please". Ah well

Thanks again
Tina