Thermostat issues

[Albert Clark]

Hey, I have a v70 rack with the thermostat set at 87.0 down from 88.5f. The humidity is at 80%. I lowered the thermostat to 87.0 bc my thermometer was reading 93.5 at the back of the tub. The thermometer is a zoo med digital. Surface temps by ir gun is 84.5 to 89.0 at various locations. Should I wait and see if the temps even out or readjust the thermostat? Thanks

[Serpentine666]

May want to consider a better thermometer/ hygrometer ? Usually get what ya pay for in herp equipment-- My personal experience with zoo med hasn't been so great.
Good luck m8!

[kitedemon]

Yes you always need to wait around 12 hours for things to stabilize. Racks are odd creatures it is always an average often the temps are never exactly what you want every where, often it is finding an acceptable range.

IR guns are fantastic tools but need to be coupled with understanding of how they work and the limitations. They do not measure plastics well, translucent shiny objects reflect IR and this is what they measure. The rate of reflection is higher than what they are calibrated for (think brown paper) and the corresponding reading can be off quite off even. I would suggest adding a bit of paper to the back as a target to measure and then remove it when you are happy. Simple and easy and removes the possible emmisifity errors and bounce errors.

What stat do you have? If I recall it is a herpstat? or am I mistaken. Herpstat, helix, ecozone, herpkeeper all have highly accurate spec'd probes they can be used to check other thermometers. Some stats learn how fast or slow a heater responds and adjusts the power curve to match. I have noticed with a newer set up and a relatively high or low powered heater it sometimes when you adjust it takes longer to stabilize as well. When it has been operating for some time in wide variety of situations it is faster. I believe this is related to the power curve still being learned.

Where you place the probe may also help regulate the rack as well. Most use the middle shelf and often the top is a bit over and the bottom under. Of course the room plays a major part in the regulation the more stable the better and often the closer to correct ambients the better. There is a reason why most larger breeders keep racks in warm humid spaces.

[C2tcardin]

My experience has been the same as Kitedemon's, you typically want to move the temp probe around and experiment with your temps. Also second the temp gun usage thoughts, though I personally think they're pretty accurate. I tend to spot check by aiming at the bare tub bottom and the substrate in the area that the tub sits over the heat tape and split the difference, unless the tub surface read really hot then I may lower temps a half a degree then check 6 hours later. I have to agree on the Herpstat as well, these things rock and are well worth the expense especially if you plan on expanding your collection in the future.

[Albert Clark]

Thanks Kite, I think I got it to level out now. I also had to relocate the probe to directly on the heat tape from inside the tub. The thermostat is herpstat 4, which spyder robotics says specifically not to place the probe on the tape. The humidity I just keep tweaking and it seems to be levelling back down.

[Albert Clark]

May want to consider a better thermometer/ hygrometer ? Usually get what ya pay for in herp equipment-- My personal experience with zoo med hasn't been so great.
Good luck m8!

O.k. I will keep that in mind.

[PitOnTheProwl]

Kite has you covered here.
Just dont make too many adjustments at one time.
I have my thermostat probes on the tape.
I also have one extra tub that has a probed thermometer in it with the probe taped to the inside of the tub over the hot spot.
This tub gets rotated through my racks so I can keep track of what every shelf is doing.

[Albert Clark]

Thanks Pit, I will try that too!

[kitedemon]

FYI...

IR guns are ok for accuracy +/- 2ºF or so generally. The part that takes a bit of knowledge is knowing when it maybe off. Basically it is just a light meter for IR 'light'. White shiney objects or metal objects have a disproportional amount of IR emission/ reflection than a dull dark objects, it creates a variation. They typically are calibrated for organics like dirt, plastics and metals maybe off possibly way off.

I have a highly accurate thermometer that is a fast response (under 1 second) so it is easy to check readings and I get to see how easily the IR guns go off. When you point the gun at a spot and move in just a few inches and you get a degree or two of change it is likely the IR gun not that the temperature is different.

Quick little article about them.

http://www.thermoworks.com/blog/2012...d-thermometry/

[Albert Clark]

May want to consider a better thermometer/ hygrometer ? Usually get what ya pay for in herp equipment-- My personal experience with zoo med hasn't been so great.
Good luck m8!

Thanks Serpentine666, I actually was looking for the accurite digital thermometer with the probe but home depot didn't have it. I then settled for the zoo med probed one from petland.