In message <9pdfvl+djik@...
> Just wondering... I have 2 12" long thermometers, and they both
> read temps. within about a degree of each other for most of the
> range, but when i put the bulbs in boiling water, one reads 99C, the
> other 96C. I would have expected them to be a 1 degree or so out,
> but 96C? Does it matter how much of the thermometer is exposed to
> the air? I know its the CONSISTENCY that matters, but this test
> would seem to suggest that ONE of them ISN'T consistant.
> (Incedentally, the one that read 96C was more expensive than the one
> that reads 99C!)
I've just had a similar problem, the 'old faithfull' thermometer (country
of origin unknown, accuracy unknown !) readings were up to 4-5 deg
different from the digital thermometer (battery flat ?). Solution - go out to the
local lab equipment supplier and buy a thermometer of known provenance,
in my case BS1704 (British Standard), known UK manufacturer & marked
accuracy - brand new & unused cost me £2 from his obsolete stock shelf. If
you suspect a thermometer I suggest changing it for one with at least some
form of national standard mark on it, all lab standard thermometers I looked
at were also marked up with a range, accuracy and required immersion (e.g.
For absolute accuracy the amount you immerse a thermometer in
hot liquid/vapour can also effect the reading (I'm not sure by how much & if
this applies to all types of thermometer) - some thermometers have a line
marked round them to indicate how far you push them in.
If still not happy then you can buy thermometers with a calibration
chart - but it'll cost you !!!!!! Hope the info is of some use.
Fra' Auld Reekie