How trustworthy are the thermostat temps?

I have a johnsons controls thermostat hooked up to both my snake tubs. I have it set for 93*. I have the probe taped to the flexwatt outside the tub. I have been measuring temps all day and I keep getting crazy readings. I have used my thermometer with a probe inside the tub and it reads 85*. I use my temp gun (I am thinking its not very reliable :/) and it says 100* and the thermostat says 93*.

WHAT IS RIGHT??

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Originally Posted by Kaorte

I have a johnsons controls thermostat hooked up to both my snake tubs. I have it set for 93*. I have the probe taped to the flexwatt outside the tub. I have been measuring temps all day and I keep getting crazy readings. I have used my thermometer with a probe inside the tub and it reads 85*. I use my temp gun (I am thinking its not very reliable :/) and it says 100* and the thermostat says 93*.

WHAT IS RIGHT??

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surface temp is always different then ambient. even probes cannot get a 100% true surface temp reading.

i notice the same thing but, believe me the temperature gun is accurate. i saw a thread about htis 2 weeks ago as well.

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Originally Posted by JeffJ

surface temp is always different then ambient. even probes cannot get a 100% true surface temp reading.

i notice the same thing but, believe me the temperature gun is accurate. i saw a thread about htis 2 weeks ago as well.

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I am not asking if the temp gun is right. It gives me erratic readings, and I don't trust it. I am asking how reliable the thermometer built into the thermostat is.

The thermometer built into the tstat is usually not very accurate. I'm not sure about Ranco's, but even my Herpstats don't give the exact reading.

The probe of the thermostat does not measure the exact temperature; it also gets some ambient temps on it.

That, and probably the fact that the Ranco is made for controlling temps and keeping them in a specific range instead of giving you the exact temperature, is probably why you shouldn't trust the temps on the tstat.

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Originally Posted by Kaorte

I am not asking if the temp gun is right. It gives me erratic readings, and I don't trust it. I am asking how reliable the thermometer built into the thermostat is.

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its reliable to its specs. but the probe is meant to meter ambient temperature. not surface. this is where the discrepancy is arising. its like comparing apples to oranges. surface temperature will always be different then the heat radiated from it.

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Originally Posted by JeffJ

its reliable to its specs. but the probe is meant to meter ambient temperature. not surface. this is where the discrepancy is arising. its like comparing apples to oranges. surface temperature will always be different then the heat radiated from it.

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a 15* difference is a bit much though, don't you think?

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Originally Posted by Kaorte

a 15* difference is a bit much though, don't you think?

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depending on how close you hold it will affect the reading too. the closer you hold it the finer the surface area it reads from if i hold it 1/2 inch from the substrate compared to an inch i can usualy see 1-2*f difference as well. 15*F might be a little bit extreme but i could be wrong could be 100% normal. i dont get that huge of a difference. but its at lease 8*f difference for me

My temps read:

Herpstat 99

acu-rite:
hot side 92
ambient 81

temp gun:
hot side 93
cool side 80
snakes core between 83-89

Took 3 days to get everything as I like it! Pretty big difference between the herpstat and ambient tub temps. I was having sort of the same issues the first few days.

I am finding that the temps are higher than what the thermostat reads.
I guess I will just be fidling some more tonight.

Just a thought is where is the probe located? Is it on the hot side or cold? Is it high or low? When my probe on my Ranco was high it caused the surface temp to be too low, but when I lowered the probe almost to the ground I was able to even out the ambient and also increase the surface temp...I notice mine off a good amount too, but all are within the accepted temps zones...And I have 3 cages hooked up to my Ranco...but I admit it is frustrating...

My problem was my temps were to low. I had my stat at 95 and ambient was mid/upper 70's and tub temp hi was like 86 or so. I'm sure you'll get it figured out it just might take some tinkering. Good Luck!

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Originally Posted by pitsandpythons

Just a thought is where is the probe located? Is it on the hot side or cold? Is it high or low? When my probe on my Ranco was high it caused the surface temp to be too low, but when I lowered the probe almost to the ground I was able to even out the ambient and also increase the surface temp...I notice mine off a good amount too, but all are within the accepted temps zones...And I have 3 cages hooked up to my Ranco...but I admit it is frustrating...

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I have the probe taped to the flexwatt outside the tub

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Try putting the probe on the bottom of the tub inside and let the temps adjust for about one hour and rechecking.

Bloodsong

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Originally Posted by Bloodsong

Try putting the probe on the bottom of the tub inside and let the temps adjust for about one hour and rechecking.

Bloodsong

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the thermostat probe? I have always read to stick it on the outside, but I will give it a shot.
*Goes and bothers my snakes some more* lol

Your aim with the thermostat is to control the temperature the snake experiences inside the tub. The probe can't help the stat do this if it isn't measuring the temp inside the tub. I just tape it under the hide and substrate with a little piece of clear packing tape to hold it in place.

Bloodsong

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Originally Posted by Bloodsong

Your aim with the thermostat is to control the temperature the snake experiences inside the tub. The probe can't help the stat do this if it isn't measuring the temp inside the tub. I just tape it under the hide and substrate with a little piece of clear packing tape to hold it in place.

Bloodsong

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Although I keep my probes inside the cages (hard to get rights temps by putting them outside the cage with an RHP and fluctuating house temps), I hot glue them to the cage.

I used to tape them, but I don't trust it at all. Partly thanks to dr del (hear that, Derek, I took your advice :gj:), but I'm really pleased with the result. Unmovable.

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Originally Posted by DutchHerp

Although I keep my probes inside the cages (hard to get rights temps by putting them outside the cage with an RHP and fluctuating house temps), I hot glue them to the cage.

I used to tape them, but I don't trust it at all. Partly thanks to dr del (hear that, Derek, I took your advice :gj:), but I'm really pleased with the result. Unmovable.

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For me the "unmovable" part is a huge drawback! I am a bit anal retentive about cleanliness so I clean the tubs once every two weeks. Taking them out and scrubbing them in a different room would mean having to move the entire setup if my stat probe was permanently stuck to the bottom of the tub.

Bloodsong

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Originally Posted by Bloodsong

For me the "unmovable" part is a huge drawback! I am a bit anal retentive about cleanliness so I clean the tubs once every two weeks. Taking them out and scrubbing them in a different room would mean having to move the entire setup if my stat probe was permanently stuck to the bottom of the tub.

Bloodsong

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Alright, I hear yer problem. Unless you have a herpstat, it'd be quite a major hassle (the herpstats have probes that you can unplug).

What would putting the thermostat probe in one of the tubs help with though if I am measuring temps with other devices (not the thermostat). I can adjust the t-stat to whatever I want and it most likely won't match up with what my setpoint is.

My problem is, I am measuring temps with a temp gun and I get 100*+ and then I measure with a probe thermometer and I get 85*. I shoot the temps right next to the probe. I don't think moving the probe for the t-stat will make any difference, I will just have to change my setpoint all around.

if that probe is put inside the tub and not secured it can be pushed away from the bottom of the tub and in turn raise the temps and possibally cause a burn! also if its taped and the tape comes lose you it can tear the snakes skin and still cause a burn on top of it!
it should be taped to the flexawatt and it should be adjusted to where the inside temps are where you want them no matter what the temp at the probe is.

Okay, let me rephrase my problem.

I am measuring temps a few different ways.
1. I have a thermometer with a probe
2. I have a heat gun
3. I have a thermostat

All of these devices are reading temps that are more than 5 degrees off from eachother. Which one should I use as a constant. Everyone is saying the heat gun but I keep getting such strange readings with it. I take a reading from the same spot and it says 100, then 98, then 95, then 100 again. That is not good. That is too much of a difference to know the actual temp.

I need to know which device I should trust to measure my temps. This has nothing to do with probe placement, I have my thermostat probe on the outside of the tubs and that is that.

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Originally Posted by Kaorte

I have a johnsons controls thermostat hooked up to both my snake tubs. I have it set for 93*. I have the probe taped to the flexwatt outside the tub. I have been measuring temps all day and I keep getting crazy readings. I have used my thermometer with a probe inside the tub and it reads 85*. I use my temp gun (I am thinking its not very reliable :/) and it says 100* and the thermostat says 93*.

WHAT IS RIGHT??

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as for this the temp on the heat tape itself should be 93.
the heat gun typically will not be accurate reading on clear surfaces.
as for the thermostat probes being inaccurate typically most are within a degree or 2 at most! if your thermometer has a probe put it next to the thermostat probe and compare them. and with the heat gun you should be able to shoot the temp of the thermostat probe itself to see where the issues are.

Have you tried going around the house with the temp gun and the thermometer? If they still give crazy readings it's either broken or the batteries are dead.

And like nixer said, temp guns don't take good readings off of reflective surfaces, so are you taking temps off the substrate or the bottom of the tub?

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Originally Posted by DutchHerp

Have you tried going around the house with the temp gun and the thermometer? If they still give crazy readings it's either broken or the batteries are dead.

And like nixer said, temp guns don't take good readings off of reflective surfaces, so are you taking temps off the substrate or the bottom of the tub?

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Bottom of the tub, maybe this is my issue.

I am going to try what you said nixer. I will be back momentarily with news.

k, the temp gun gave me 94 next to the thermostat probe that was reading 92. So that sounds a little better.

I think it might be the reflectiveness of the tub that was throwing it off. Digital probe is hovering around 85 though :/

Waaah this is so frustrating D:

Like I said before, the digital probe measures roughly half surface temp, half ambient temps.

I only use my thermo/hygros to check up on temps and to see if the stats are doing what they should be doing.

I use my temp gun to check for the actual temps.

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Originally Posted by Kaorte

k, the temp gun gave me 94 next to the thermostat probe that was reading 92. So that sounds a little better.

I think it might be the reflectiveness of the tub that was throwing it off. Digital probe is hovering around 85 though :/

Waaah this is so frustrating D:

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you think that is bad i have 3 of those on my incubator and my herpstat 2
my herpstat 2 reads 87.8 one thermometer reads 87.6 and the other one reads 73.6 and my temp gun reads 88

do you know now what you should be going by

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Originally Posted by nixer

you think that is bad i have 3 of those on my incubator and my herpstat 2
my herpstat 2 reads 87.8 one thermometer reads 87.6 and the other one reads 73.6 and my temp gun reads 88

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Hmm.... I wonder which one is wrong....:rolleyes:

I just hate this guessing game crap!
I just want to build my rack and get everything stabilized!!
Right now I have two tubs next to eachother. Both tubs read different temps. Argh.

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Originally Posted by Kaorte

I just hate this guessing game crap!
I just want to build my rack and get everything stabilized!!
Right now I have two tubs next to eachother. Both tubs read different temps. Argh.

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thats also why there is such a big range for the warm side. id set thermostat like 2-4 degrees over the temp your wanting and put a piece of paper towl in there and shoot that typically it wont be but maybe 2 degrees over what the tub bottom is with the paper flat on the bottom and no space between the tub and the paper

Quote:

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Originally Posted by Kaorte

I have a johnsons controls thermostat hooked up to both my snake tubs. I have it set for 93*. I have the probe taped to the flexwatt outside the tub. I have been measuring temps all day and I keep getting crazy readings. I have used my thermometer with a probe inside the tub and it reads 85*. I use my temp gun (I am thinking its not very reliable :/) and it says 100* and the thermostat says 93*.

WHAT IS RIGHT??

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yea with my thermostat its at like 104* and the thermometer in her hide says 91. i guess there not that accurate.

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Originally Posted by bamf64

yea with my thermostat its at like 104* and the thermometer in her hide says 91. i guess there not that accurate.

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My Ranco probe taped with aluminum tape to the flexwatt Reads 98-102 (I switch it around because the A/C runs colder at nite)

The accurite probe reads 91-94 under the warm hide. The thing is though, without the hide the probe will reach 88 at the most.

I though I was the only one with this problem because I am new at this. Hell I just assembled my Ranco about a week ago lol.

Oh and yeah I dont own a temp gun yet, I am gonna try to buy one this weekend.