Personally, I'd stick to what the chiller manual calls out for along with following the maintenance schedule. This will result in longer life, less downtime and lower operating costs.

We run the recommended mix of distilled water and DowFrost glycol in our CO2 chillers. Also I would recommend the use of a anti-biological agent to keep algea/microbial growth at bay. Unchecked growth can easily clog the pump filter screens.


-AK2DM

 

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"It's the questions that drive us"
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Be careful- certain machines need specific maintenance on the cooling water. Some must use plain deionized water with special filters, some use special chemicals. Not maintaining the cooling system has done some of the most extensive damage I've ever seen in over 23 years service.

there are parts on all machines that if you don't maintain, you may be down for a few hours and a few $. I've seen cooling water issues take out machines for days and cost tens of thousands of dollars. It's a quick way to cause need a resonator replacement on a trumph for sure. I've seen bad water eat through 12mm alu. Look at all the alu parts in your machine that have water in them.

crappy grounds between all the components that are in the water loop can cause erosion too. Ground the chiller to the cabinets and resonator if there's any voltage potential between their chassis.

Chris Krug http://krugtech.com/
Maximum Up-time, Minimum BS

Thank you guys for your input. I was slightly mistaken about what was going on. The chiller was originally filled with the correct mix of Dowfrost/distilled water. However, when topping off the chiller after that, the correct mix was not observed.

The more concerning thing is that the last time the fluid was swapped was back in 2005. Our lines appear to be decently clean, and we don't run the laser much, (Under 3000 beam-on hours since 2004) so it doesn't appear that the fluid has broken down. Either way, it will be flushed very soon.

The water tends to evaporate.  The DowFrost stays you should usually just add water.  Change the water yearly.

this is really risky compared to the few $ you are saving, if manufacturers tell you should use mix distilled water / glycol it's also because if the chiller system gets frozen, you'll have a very expensive maintenance to be done, you'll also have to stop production for some days. Not worth it