The most important thing you can do is keep the dust filters clean and make sure the condenser coil is clean. There isn't really anything to service. It's really not any harder than keeping your computer clean. Compressed air will do the trick. Since it is a sealed system, there isn't a need to check the Freon unless it stops cooling. Freon doesn't wear out or get used up. They don't even put service ports on them unless it is a commercial model. If it isn't cooling as good as it once did, most likely the condensing coil is dirty. If the coil is clean and its still not cooling, you probably have a Freon leak and you might as well buy a new chiller. Make sure you unplug it before opening it up.
