Heater issues?

[ib4walrus]

Calibrating the thermometer right now, can't believe I didn't remember using the freezing temperature of water as a calibration point (when I did a whole lab to know the importance of calibration -_-). Slly me, for some reason I thought 78 F would be hot, sorry disregard what I said earlier about the cold feeling.

 

[ib4walrus]

Woah, apparently the thermometer is wildly inaccurate. After using freezing water, the reading point is so low that I'm approximate it to be about 15-20 F off. Looks like I gotta run out and get a new thermometer pronto. The brand I bought was the Penn Plax floating thermometer, is this just an anomaly or would I be safe in getting another one of these? Would digitals, the stainless steel hook on, or the stick on (though I can't see why this would even work) be more reliable?

If it turns out to simply be the thermometer's reading, I'll be able to sleep easier about my heater.

 

[Bubbles2112]

I like the digital thermometers myself--but having said that, I have a back up thermometer just in case.

 

[Hebily]

if you have an acrylic tank, a stick on will NOT work. the one's that suction cup to the inside of the tank are great, or another floater... you don't need anything fancy, just accurate. in the package at the store, they should all read the same...

 

[sapphire384]

ive always used the weighted thermometers. interesting thread though that possibly a thermometer could be wrong and not the heater.

 

[Hebily]

alcohol thermometers don't really go out of calibration (unless it cracks!), but it could have been messed up from factory. or the scale could have somehow gotten moved relative to the tube (i.e. the glue came loose, or it got bumped pretty bad)

 

[SMinNC]

After a few heater installs. I'd pretty much given up on setting them by their numbers.

And after placing 6 New (floating)thermometers in a tank. I don't trust them either. I got at least 4 diferent readings. Varying about 4 degrees.

What I do, do, is.

Get that thermometer, I have a little trust in. Put it on the tank with the new heater. Adjust heater according to the thermometer. And not worry if the heater says 73* or 90*. As in. Right now I couldn't tell you what heater I have is on what temp "setting".

Temp to the touch works out pretty good after you get used to it.
I like to think of it in kind of a pH, kind of way.
Right about 80* would be pH 7. It has that neutral feel to it. Below has a cool feeling. Above has a warm feeling. : )

 

[Hebily]

something else you can do to help ensure the accuracy of your thermometers is have redundancy. Have say 4 different thermometers, one in each corner. Depending on your current, they will probably read a little differently, but that way, you can keep the average temp where you want it, and if one therm changes temp and the others don't you know there is a problem. also, I know with my heater that the above post is right. that brand (I don't remember what it is, but I have two of them) both say they are set for 81 F when the tank is at 78.