Temperature Control For Distinguished Lab Managers, Pt. IV: Internal Vs. External Immersion Circulators

After our previous post about polycarbonate vs. stainless steel bath tanks, we’re going to finish up this “distinguished lab managers” series with some guidance on immersion circulators.

Specifically, we’ll shed light on the differences between internal immersion circulators and external immersion circulators, plus what to look for when choosing a unit that fits your application requirements.

Internal Circulators

For internal processes, you’ll be immersing the application or sample(s) in the bath tank for incubation/testing. This will require an immersion circulator for internal temperature control.

So, what matters when choosing an internal circulator?

• DIMENSIONS
  Make sure the unit has the appropriate internal bath tank opening dimensions for the immersed sample(s)/application.
• TEMPERATURE
  Make sure the unit’s working temperature range and heating/cooling capacity fit your application’s requirements.

External Circulators

For external processes (condensers, jacketed vessels, platens, battery packs, etc.), the tempered bath fluid will be pumped by the temperature control unit to an external fluid loop, and then returned to the unit. And this pumping is done by an immersion circulator with an attachment for external temperature control.

What’s relevant when deciding on an external circulator?

• TEMPERATURE
  Make sure the unit’s working temperature range and heating/cooling capacity fit your application’s requirements.
• BATH FLUID
  Don’t forget to take your bath fluid into consideration. For silicone oil, bear in mind possible expansion/contraction of fluid volume when exposed to different temperatures. For applications using water or water/glycol bath fluid, select the unit with the smallest bath tank available

Gotta control it all?

It goes without saying – although we will say it, just to be thorough – that you have to consider all the factors above if you’re choosing a circulator for both internal and external applications.

And that concludes our “temperature control for distinguished lab managers” series! We hope you enjoyed reading these four blog post as much as we enjoyed writing them. As always, your feedback is highly encouraged! Not only does it let us know how clear and helpful we’re being (very important!), but it also helps dictate topics to cover and questions to answer in future posts. Thanks in advance.

Still have questions? Ready for decisions? Learn more about JULABO USA by visiting our site at julabo.us.