temperature swings

[gnatp2]

I have a 120g tank in a frickin hot apartment. For temperature control, I am using a 1/3hp aqualogic chiller. It does a great job keeping the tank between 79-82 degrees. I always thought that my tank temperature was stable, but then I started thinking that my chiller goes off/on every 10 minutes or so. That means that my tank is 79 degrees, then 82 degrees 10 minutes later and then right back down to 79 degrees 10 minutes after that. Makes me think that my temperature is no so stable after all.

What do you guys think?

Nate

 

[crox99]

It's almost impossible to raise the temperature by 3 degrees in 10 minutes on a 120 g unless you keep a burner underneath it.

 

[Aqua Pro Builder]

Is the temperature probe in the tank or internal to the chiller?

How you connect the water in and out?

Both will greatly affect how the chiller turn on and off.

 

[Wes]

let me guess, do you have your chiller hooked up like this?

sump -> chiller -> sump

if so you are basically cooling the sump quicker than the rest of the water causing your chiller to turn on and off frequently...which isn't good for your chiller. The temp in the display is probably holding pretty steady but temp in the sump swings drastically.

 

[gnatp2]

Yup, that's how I have it set up. Now it makes sense. Time to change some plumbing.

Thanks guys,
Nate

 

[DallasNYC]

Where do you have the temperature probe. I would think if the probe is in the display tank, then it wouldn't matter how the plumbing is done in the sump?

 

[gnatp2]

Where do you have the temperature probe. I would think if the probe is in the display tank, then it wouldn't matter how the plumbing is done in the sump?

temp probe is in the sump as well, contributing to the problem

 

[kimoyo]

Changing the probe to the tank will just make the chiller stay on and go off longer. So instead of 10 minutes, you'll have it going on/off for 20 minute periods. But the real issue is that a 1/3 hp chiller shouldn't be working that hard on a 120. My 120 used that same chiller and it didn't go on/off that much. Look at how much electricity your putting in the tank and if its worth it. What pumps are you using?

It's almost impossible to raise the temperature by 3 degrees in 10 minutes on a 120 g unless you keep a burner underneath it.

He has 2 400W bulbs over it. The water volume of a 120g isn't big enough to handle that and all the other electrical/heat input.

 

[bad coffee]

I did the same thing on my 58. sump > chiller > sump. When I switched to sump > chiller > tank, My chiller did a lot less work.

B