Temperature Question

[martin82531]

Hello,

So I received my thermostat today (http://www.amazon.com/gp/product/B00...ls_o01_s00_i00)

I had to use some couple of pieces of wood that I had cut at home depot so I could raise my tank a few inches from the tank stand, before the tank was sitting direct on the stand which would not allow for my UTH to be placed directly under the tank due to the lack of space to allow the escape of the excess heat. Previously the UTH had to be placed on the side of the tank.

Once I had everything set up I was monitoring the thermostat and seeing how the temp fluxuates. I set the temp to 91 degrees, I noticed the once the thermostat shut off my UTH the temp would continue to raise to 92.6 degrees, then (even though the temp was set to 91), and it would not turn on the UTH until 88.8 degrees. I understand the thermostat I purchased is on the low end of what I could have bought, but I was wondering if these temp ranges are ok for the hot spot for my tank.

Thank you,

Greg

[kitedemon]

I don't like seeing that much variation i can live with a degree but 3 is a bit much. this is common with hydrofarms they seem to shut down 2 degrees over the set point and 3 under it. They are not great units this swing might be reduced by heating the room ambient temp a few degrees higher, try lifting this to 78-80º and see if it improves.

[The Serpent Merchant]

Sounds normal. This is an issue with the on/off style thermostats like the one that you got. Higher end proportional thermostats don't have this issue.

While not prefered the temperature flux you described will not be an issue.

[martin82531]

Sounds normal. This is an issue with the on/off style thermostats like the one that you got. Higher end proportional thermostats don't have this issue.

While not prefered the temperature flux you described will not be an issue.

Do you think I should use a secondary heat source to help with the temp flux? The only issue I have had so far with using one (e.g. light bulb) is it seems to suck the humidity out of my tank.

[The Serpent Merchant]

If the cool side of your cage stays between 78-82 degrees I wouldn't use a secondary heat source. If it stays below 78 then I would consider it.

[martin82531]

If the cool side of your cage stays between 78-82 degrees I wouldn't use a secondary heat source. If it stays below 78 then I would consider it.

Do you think I could raise the thermostat to 92 degrees? The only concern I would have about this is, once the thermostat shuts of my UTH the temp could continue to raise till 93.6 degrees, would this temp be too high?

If this is not too high, the UTH would turn on back a 89.8 verse 88.8 degrees.

[The Serpent Merchant]

I wouldn't turn it up, it's not like the temps stay low all the time. I am more worried about high temps vs low temps.

The ideal range for the hot side is 88-92 degrees so you are still fine.

[kitedemon]

It would then shut down around 93 or so? No I would not the other hydrofarm issue is the reading is horribly off. I have tested a number and I have not had one that was correct. They all read wrongly. Johnsons and rancos both only have a one degree up and down shift and are better for accuracy. proportional units are even better again. I don't usually suggest using a hydrofarm they just have such poor accuracy and swing that makes them iffy.
26.9ºC = 80.42ºF the hydrofarms in the picture are 83.8 82.4 and 81.6.

Hosted on Fotki

[martin82531]

I wouldn't turn it up, it's not like the temps stay low all the time. I am more worried about high temps vs low temps.

Very good point, especially I'm in Phoenix, AZ. Cool temps are not much of an issue here

[martin82531]

It would then shut down around 93 or so? No I would not the other hydrofarm issue is the reading is horribly off. I have tested a number and I have not had one that was correct. They all read wrongly. Johnsons and rancos both only have a one degree up and down shift and are better for accuracy. proportional units are even better again. I don't usually suggest using a hydrofarm they just have such poor accuracy and swing that makes them iffy.
26.9ºC = 80.42ºF the hydrofarms in the picture are 83.8 82.4 and 81.6.

Hosted on Fotki

The hydrofarm shuts off at 91 degrees which is what I have it set to, I think its just the "left over heat" from my UTH that admits and that gets the temp close to 93 degrees before the temp actually starts to drop.