Thermometer

[Mr.Everready]

I've been using a Richies spirit thermometer since i started my kits 3 or 4 months ago. Last week I bought a digital proble thermometer, it turns out my spirit one is reading 5c lower than it should. :?
I've said before that my brews aint been great, drinkable but not great ( could high tems cause problems with taste ? ), especially after a few weeks in the bottle ( when everyone is raving about their beer ). My aquarium heaters in the waterbath have been set alot higher than they should have been, I was blaming their thermostat all along having to set them to 25-26 to get a 20c bath.

Even when I tried the digital side by side with the spirit I assumed that the digital would be wrong and tried to find out how to calibrate it

So in essence, it's just another thing I should have checked at the start, along with my measuring jug and FV measurments.

 

[Kev888]

Thats interesting coincidence - I got a cheap 'meat' thermometer recently and thought i'd test it to see how accurate it was... It wasn't at all.

No real surprise, but I discovered in the process that out of the 7 thermometers I have only three vaguely agreed; even ignoring the cheapo one which was just stupid, the range was about 16 degrees C in disagreement!

So I tested them in boiling water and the three that agree did seem to be accurate at that end of the scale. Apparently you can use slightly thawed ice to test the zero end and so verify if they're linear, but I don't have a freezer at the mo.

Cheers
kev

 

[Mr.Everready]

I'm getting a loan of one tonight from the wife who's a nurse. If her's are wrong too then I've no chance.

 

[dennisking]

I'm getting a loan of one tonight from the wife who's a nurse. If her's are wrong too then I've no chance.

I would ask on what part of the body she uses it. :shock:

 

[Vossy1]

Apparently you can use slightly thawed ice to test the zero end and so verify if they're linear, but I don't have a freezer at the mo.

Yep, fill a (preferably insulated) cup/ice bucket/flask with ice, add water, but not so much as the ice floats, stick your thermometer in and stir like crazy (I stir with the thermometer).
It may take a few minutes to get to 0 deg ish, but it will get there and try to make sure your thermo isn't touching the sides or base of the ice holder.
It's still worth doing the boiling test as accuracy can vary at each end of the scale.

 

[oldbloke]

So... My aquarium heater is set to 20, my thermometer says it's giving 22, and both may be wrong?
How accurate are the lcd-strip ones?

 

[evanvine]

How accurate are the lcd-strip ones?

Most seem to have a window every 2 degs, so looks like it's +-1.

 

[Mr.Everready]

Not tried the ice water but I as ir happened the thermometer she had only went from 35 -42c. I filled a cup with warm water and it was spot on 37c, I put in the digital and it was 37.something the spirit was 32
So it looks like my heaters have been spot on for the last few months, over cooking the kits I've done in that time

 

[golder247]

I use the LCD strip one on the side of the bucket and it has served me pretty brilliantly so far.

I am only a kit man but I am not sure that it is incredibly vital (to have exact temp) as long as you are within a couple of degrees of your optimum... I could very well be wrong but not had a brew fail me yet, and all this because my therm had been stored on its side by a previous owner and I was too cheap to buy a new one.... trying to fix by freezing etc. had about 8 strip therms from when the little man was born and thought I would just stick them on my FV.

They are really helpful to use as you have a constant reading which you don't have to open a lid for.

 

[Kev888]

just to mention; resolution and accuracy are different beasts. Its possible to have a themometer with tiny little graduations/steps but still be wildly out - fairly pointless but quite common, especially with digital stuff as its cheap to have more digits but no so cheap to calibrate properly. And it makes the buyer think its better - to be honest whilst i know this, it probably still caught me out anyway; I really should have tested them earlier!

Happily the ATC800 I have on my fermenting cupboard is more or less right. My house/garage vary quite a lot and I'd say that sorting out a controlled/stable fermenting environment (the usual freecycle fridge affair) has made the biggest improvement in consistency to my beer for years.

Cheers
kev