Did I ruin my stick-on thermometer?

[kombat]

Like most of you, I have those stick-on thermometers on my fermenting carboys. The last couple of batches I brewed, I set the carboys in rope tubs with water, covered with a wet t-shirt, to keep it cool during primary. During primary, the stick-on thermometer on the carboys would have been below the level of the water in the rope tub it was sitting in.

Last night, I removed the carboys from the water baths and dried them off, to finish fermenting at regular room temperature (60-65 F). All of the numbers on the stick-on thermometer had a light grey background instead of the usual jet black. I figured maybe the carboy was simply unusually cold, and once it dried off and warmed up a little, it would go back to working normally.

However, this morning, the stick-on thermometer strip still has a light grey background behind all the numbers.

Are these things not waterproof? Did I ruin them? Or will they eventually start working again?

 

[comrock12]

Pretty sure the thermometer is ruined. Good news though, they sell them at pet stores in the fish area if your local homebrew shop is too far away. They are like 2-3 bucks a piece so pick up a handful.

 

[duboman]

Yup, worthless now so replace them, measure the water line and place them just above that line!

 

[billl]

Yeah, you would think that thermometers designed for fish tanks would be waterproof - but no such luck.

 

[unionrdr]

I always thought that maybe they don't have a water proof coating on the liquid crystal stuff on those lil squares. the water seems to nutralize them. But the local Petsmart can be handy. They have 2 different sizes of stick on thermometers,3-packs of lift tube cleaning brushes (good for cleaning plastic tubing,auto siphons,spigots,etc),Heaters that some use in swamp coolers. That kind of thing. Everything works if ya let it!

 

[BigRob]

Save your money and don't bother to replace em, they last for a batch, then get ruined when you wash the carboy or bucket. Buy a digital instant read, and take the temp of the water bath, you'll be within 1-2F of the internal temp of a carboy, and 2-3F of a plastic bucket. Make sure the thermo is calibrated properly out of the box too.

 

[unionrdr]

Not true as long as you don't submerge the FV in water to clean it. I wipe down the outside with a cloth dampened with PBW to clean,avoiding the temp strip. I still have the original ones I started with.
Having said that,I did see midwest selling this plug like thing with a long needle like tube that goes down into the FV. It is intended to sit in the middle of the wort,& a temp probe is lowered into the inside of take temp readings. Here's the link; http://www.midwestsupplies.com/stopper-thermowell.html

 

[aubiecat]

I used these before I built temp controllers. The probe is submersible and they are accurate withing a degree or two.

 

[BigRob]

I've never submerged my carboys, but the strips stopped working after they overflowed with PBW while filling. I guess if you want to be really careful you can make them last, or perhaps you've got better strips than I had.

However for the price of a few strips, you can get a digital that is more accurate, and useful for other things like mash temps, cooking, etc. There's a few threads on HBT regarding the temp differential across glass/plastic FVs in water baths, and in general just monitoring your water bath temp gives you a pretty decent idea of the internal FV temp.

 

[RM-MN]

i bought a non contact thermometer like this one for other purposes but it works for brewing too so it's a win-win situation. I bought mine from a USA seller and paid a little more for it. just point it at the fermenter and pull the trigger.

http://www.ebay.com/itm/Digital-Non...067?pt=LH_DefaultDomain_0&hash=item2ec3a4385b

 

[beergolf]

I have submerged a few buckets in a water bath and the strips turned all grey. The funny thing is they did come back after they got good and dry again.

 

[andycr]

That happened to the first temp strip I had. Since then, I covered my strips with clear packing tape. It's invisible, and I haven't had a strip go bad since.