Troubles With Lytron Kodiak Chillers

While this post itself might not be too lasertastic, hopefully it spare someone from the pain and frustration that my lab has had to go through regarding Lytron chillers.

Just for a little background, Lytron Kodiak chillers seem to be the standard chillers that come with laser systems produced by Spectra-Physics/Newport. We currently have three in our lab, but the most trouble has been with the chiller hooked to our Evolution pump laser for a Spectra-Physics Spitfire. Here are a list of a few problems we've had and how to fix/prevent them from happening to you.

1. The PVC t-joint that contains the thermocouple for the chiller is prone to break. Cracks usually occur at the top of the t-joint where the compression fitting for the thermocouple is. There is a small groove at the top of the joint that seems to be the culprit. Lytron offers newer replacement fitting that don't contain this groove, but if you've got the dark gray PVC t-joint you should consider replacing it or at least keeping a close eye on that piece.

2. The brass pump heads contain a graphite impeller that has a tendency to slough off graphite into the chiller lines. These particles can build up in your laser cooling lines and create all sorts of problems (Don't worry, I'm already planning another post discussing all those problems). You can purchase a stainless steel pump head for around $300 from Lytron that doesn't have these same problems. Considering it's a relatively cheap part in comparison to the cost of your laser, it's worth the money to replace it.

3. In an attempt to also avoid getting particulate matter into your chiller lines your should also upgrade your filtering system to include both 5 and 1 micron filters. IF YOU DON'T HAVE ANY FILTERS GET SOME NOW! You'll most likely need to get another filter basket to house the additional filter, but they're pretty easy to find at the Home Depot. The 1 micron filters however, you'll probably have to buy online. Once again, this is a pretty inexpensive upgrade to your laser that will keep it running smoothly.

4. One last note, don't have ever add dilute HCl to your chiller reservoir in an attempt to flush out algae. You'll get the algae out sure, but the HCl will also corrode the Teflon chiller lines, or at least the ones in an Evolution. And no, adding the HCl was not my idea. I would recommend Nalco Cleanser for that purpose. I would pretty well. Just make sure you dilute it first. About 19 mL per 1/2 gallon of water is the recommended concentration.

I hope someone finds this useful. Not taking care of these things put my laser out of commission for 6 months. Even almost another 6 months later we are still occasionally feeling the repercussions of poor chiller maintenance and construction.

Best of luck lasering,

JP