We all know how important it is to have accurate temperature readings throughout the whole brewing process but I was wondering if any of you guys could recommend a reliable and long lasting brew thermometer. During my last brew day I decided to get a second reading during the mash with a second thermometer and was surprised that they showed a difference of 2C. I tested them both afterwards in a glass of water and it was the same so it wasn't down to positioning in the mash. Both are digital, one with a probe on a wire and the other the stick type. 2C might not sound much but its enough to make me feel uneasy. If any of you guys know of a good and reliable thermometer out there I'd really appreciate your tips. Cheers. Paul.
Inaccurate Brew Thermometers
- Thread starter Amidared
- Start date
Help Support The Homebrew Forum:
Have a look at this thread - http://www.thehomebrewforum.co.uk/showthread.php?t=61093&highlight=thermometers
No worries, the one MyQul links to has some good reviews and a decent price.
Yeah those do look good Chippy. I've ordered a floating thermometer but will probably get one of the digitals too. I don't think I could trust just one after seeing how the others worked, or didn't as the case may be.
MyQul
Chairman of the Bored
I'm quite happy with the dealink one so far :thumb:
IainM
Landlord.
Someone over on BIABrewer tested 11 thermometers at 7 temperatures, 10 of which were specifically sold for brewing. The range between them at mash temp was a disturbing 6C:
http://www.biabrewer.info/viewtopic.php?f=53&t=783&p=9397&hilit=+Lylo+test+#p9397
The best ones were digital probes, which I managed to identify after a bit of googling, but unfortunately they aren't made any more. I've only got a couple of glass ones and a meat thermometer which worked well for making candi syrup. I'll be sure to compare them for consistency on the next brew.
http://www.biabrewer.info/viewtopic.php?f=53&t=783&p=9397&hilit=+Lylo+test+#p9397
The best ones were digital probes, which I managed to identify after a bit of googling, but unfortunately they aren't made any more. I've only got a couple of glass ones and a meat thermometer which worked well for making candi syrup. I'll be sure to compare them for consistency on the next brew.
Hoppyland
Senior Member
My advice is to buy a mercury-in-glass laboratory thermometer from a scientific supplier that has certified accuracy (Fisher Scientific or Jencons should be OK).
Once you've got it then don't use it!!
Well, only use it to calibrate your other, cheaper thermometers. Then you're not likely to break it (or get mercury in your beer!)
You have to check your thermometers over the full range you intend to use them, though. I have a spirit thermometer that reads 2C too high at my fermenting temperature of 18-20C - but reads low at my mashing temperature of 66-68C!!
Also, a glass thermometer's inaccuracy is unlikely to shift (until you inevitably break it), but I would check a digital one quite regularly. (Having said that, I use a cheap digital thermometer to keep tabs on hatching hen's eggs - a lot more critical than beer! :))
Once you've got it then don't use it!!
Well, only use it to calibrate your other, cheaper thermometers. Then you're not likely to break it (or get mercury in your beer!)
You have to check your thermometers over the full range you intend to use them, though. I have a spirit thermometer that reads 2C too high at my fermenting temperature of 18-20C - but reads low at my mashing temperature of 66-68C!!
Also, a glass thermometer's inaccuracy is unlikely to shift (until you inevitably break it), but I would check a digital one quite regularly. (Having said that, I use a cheap digital thermometer to keep tabs on hatching hen's eggs - a lot more critical than beer! :))
They do look good but I'm really wary now of putting my faith in any one thermometer.
6C is really a bit more than 'disturbing'. When you read how specific people try to be with their recipes then you realise that they could be mashing out way above the supposed level and producing all kinds of off flavours. I mean, when a thermometer is so out, whats the point?
I've gone back to the floating non digital but I still got my doubts. I mean, we all try to be so specific about our brews and mashes but when the thermometer is so far out it just makes it all seem so pointless, like we should be going on gut instinct. That doesn't exactly fill me with confidence when I want to try and do that last brilliant brew again. You say you have a thermo that reads 2C too high then reads low, thats what I mean, whats the point and how do you we know when its reading low or not? A couple of degrees out, especially Centigrade, and the whole recipe is pot luck. I get what you're saying about using a good thermo to calibrate the cheapos, but again, the point? In this day and age why cant we just get a reliable thermo at a reasonable price without having to check one against another.
