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Maintenance Matters: Baths & Chillers

Because baths and chillers are such a basic piece of laboratory equipment, it’s easy to put them in a corner and forget about them. But, as with other instruments, maintaining your bath or chiller is extremely important.

Rachel Muenz

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Don’t forget to clean your air and fluid filters!

“Very often people don’t think that chillers and baths are the most important things in the world and probably they aren’t,” says Dirk Frese, director of sales and marketing at Julabo (Allentown, PA). “But if they [users] have a process relying on temperature control, [chillers and baths] become really crucial.”

He adds that a poorly maintained unit could take down a pharmaceutical manufacturer’s setup, for example, possibly leading to the loss of millions of dollars in drugs.

Luckily, the most important part of caring for your chiller or bath is simply keeping the unit clean, whether that’s cleaning the air and fluid filters or the condenser. Surprisingly, cleaning is something many users fail to do.

“Maintaining clean fluid, at the right level is crucial to product performance,” says Kelly Gibbons, marketing coordinator at Polyscience (Niles, IL). “Additionally, it is important to note that some fluids may lose their heat transfer properties and become less efficient over time.”

How often users should check their unit for problems depends on the applications they are using it for.

“We recommend that filters and water level are inspected weekly; however, in a harsh environment, it may be necessary to check more frequently,” Gibbons says.

Frese adds that users should also vacuum their condenser at least once a week in a manufacturing setting, but in a cleaner lab setting, they can likely get by with cleaning a couple of times a year.

Placement of the chiller or bath is also important and is another common mistake users make. Julabo units, for example suck in air in the front and pump it out the back, so they need enough space at the back to vent properly, whereas Polyscience units require enough space on both sides to vent.

“Having enough room in the back to allow that hot air to escape and not circulate back into the unit is key,” explains Ernie Stark, Julabo’s inside sales manager.

Ambient temperature in the location is also important.

“Ambient temperature should not exceed manufacturer recommendations so the unit can perform to specification,” Gibbons says, adding that maintenance aspects like physical location only need to be checked every six months or so.

Apart from dust in the air filters and on the condenser, there are several other signs that you should probably do maintenance, including dirty fluid and/or algae in the circulation fluid and loss of cooling performance, the experts say. As well as color change and turbidity, small black globules in the fluid are another sign it needs to be changed, Stark adds.

Maintenance Program Options:

  • Not all manufacturers offer such programs, but many have options that range from basic care to more extensive service
  • Extended warranties are important considerations, especially for those who expect rough use of their chiller or bath

Important Resources to Consult:

  • The operator’s/service manual
  • The manufacturer—service technicians, customer service and sales reps

“If they have it [chiller or bath] connected to a reactor, and it’s a clear glass reactor, they’ll see these little black spots,” Stark explains. “And of course their performance will go way down so they should know something is wrong.”

Gibbons adds users should make sure to refill the reservoir with a fluid that meets their application requirements.

“These mistakes can be avoided by setting and adhering to the maintenance schedule and consulting the manual, especially when it comes to things like compatible fluids,” she says.

Though they may seem unimportant, doing annual maintenance on your chiller or bath is imperative to meeting your lab’s objectives.

“It’s easy to forget or put maintenance off until ‘tomorrow,’ but too often we see units come in for repair in very poor condition due to lack of maintenance,” Gibbons says. “They end up being scrapped because of catastrophic failure due to a lack of preventive maintenance.”