This is an inside system, no dirt and the room is clean for a factory. There is also a cartridge filter in the loop. It looks clean other than the dark glycol solution. I have a new drum of glycol (30%) on site. I'm just waiting for them to give me a shutdown.
i see, the water will get dirty looking and as long as there are no particles i guess your fine..Normal...but i would still get the water tested and analyzed to make sure you are controlling corrosion and bactria.
Hands, drain the system and fill with fresh water, add a product called Citranox for cleaning. I try to run the cleaner for 24hrs at a elevated temperature for the best results. After its clean pull the top and wash the tank out very good and drain several times. Try to get all the tap water out of the system, then use a 50/50 mix of distilled water and propylene inhibited glycol.
Stay on top of the 50/50 mix and maintain.
BTW, I use Protek 100 in all my open loop chillers.