[KarlK]

As a refrigeration mechanic, I think I may know what's going on with this fuse blowing. If you don't mind, I'll ask some questions.

1) What is your differential set at (2 or 4 deg)?

2) Are you blowing a fan directly onto the chiller?

3) How much flow do you have through your chiller (really)?

I think that what may be happening is the compressor is trying to start before the high and low side pressures have had time to equalize when the chiller shuts off. The little compressors they use on these chillers (the same as in window air conditioners) are not meant to start under load. If they are required to start under load, they just sit and hum until they either trip on their motor protector (if they have one) or blow the fuse.

You can check for this yourselves. When the chiller shuts off, listen to it closely. Put your ear right up to it. You should hear some hissing for a little while. Keep listening until it tries to start again. You'll hear a little click as the relay engages to start the compressor. After that, if the compressor doesn't start right away, you should hear it hum, then it will stop after a little while when the protector or the fuse cuts it out.

There is something avaliable to help this. They are called "hard start kits". I use them on compressors of this type that have a problem starting because of high starting load.

I mentioned the temperature differential because a larger differential will allow more off time for the comressor and more time for the pressures in the system to equalize.

If you blow a fan directly onto your chiller coil, it will also help to equalize pressures faster; As will having higher flow through the chiller.

I hope that this helps. I see that there have been no new posts since the 15th, so I assume no one has had problems or they are just sick of the units.

Let me know if this info helps you. Without actually seeing the units and hooking up some guages to them, it is hard to tell. I wouldn't mind knowing if this is the problem.