[EDoucette32]

Hello! This is my first post so bear with me. I am trying to troubleshoot a FX20 that seems to be having a chiller problem. I am also jumping into the middle of this issue so I am playing a bit of catch up, again bear with me.

We have a FX20 EDM that seems to be having a problem with it's chiller. Unfortunately I have no manual for the chiller. What happens is that we get an "E1" error on the chiller control board and it is an un-resettable error... the machine needs to be powered down and restarted. This error is so erratic, at times the machine will run for hours and then it will trip every 5 minutes. Yesterday I sat with the operator of the machine and watched the display (as I understand showing the differential between the ambient air and the water) it was bouncing between .2 to .3 but never more than that and then it came up with the "E1" error and shut down. I would have expected to see a ramp up to the 5 degree trip point.

A call to Mitsubishi tech support came with an over the phone condemnation of the chiller and a comment about how there are no parts available. What they had us do was disconnect the chiller compressor from the VFD and run a test part for 1.5 hrs. We did that with no issues. Then they wanted us to reconnect and try running normal. Of course the water was too hot to do that test as we had a constant "5.F" error... but I am guessing that when I do get to run normal again it fails.

Anyone have any ideas? Any way to test the controller board? The model of the chiller is "Unit cooler, HE-UV3". At this moment I have no documentation on it.

[underthetire]

E1 on a Mits VFD is external alarm triggered.
http://www.acpd.co.uk/sei/s/1488/mit...s%20manual.pdf
So, if its a Mits VFD for the compressor, i would start by looking at the alarm signal from the machine to the VFD. Could be a bad relay contact, or something in the machine shutting down the chiller, not the chiller actually going in to alarm.
I believe one of our EDM's is an FX20, when I get a chance, ill see if we have the chiller manual.

[Makrep]

An E1 alarm on that chiller usually means that the compressor shell has overheated,(you can see the simmer stat on the top of the compressor) and the mits tech guy is right there are no parts available to repair it, here in the UK we usually advise customers to either purchase a new chiller like the one thats fitted to the new machines, or to fit a standalone chiller that can be set at 20 degrees and put a length of 10mm copper tube into the bottom of the dielectric tank connected to it to use as a cooling coil. I hope this is of help.

[glbreil]

I have no experience with the Mitz chiller but i have a lot of refrigeration experience and if Makrep is correct that E1 is in fact a sensor on the compressor shell then I would be looking at basic refrigeration issues. Start by checking the condenser coil. I am assuming it is air cooled, is it dirty? You should be able to see light through it, they have to be cleaned. Blow it out with compressed air.

Is the condenser fan running or any other issues that reduce air through the condenser. Did somebody lean card board against it have the filters been changed etc.

If all of that is okay it could be low on refrigerant. Return gas from the evaporator cools the compressor so is the suction line on the compressor cool? Have someone check the refrigerant and the compressor valves ect. Parts for the cooling side may be available or there are probably substitutes.

If every thing is fine and just the switch is bad and not available just bypass it and let it run. It only protects the chiller and you are planning to toss it anyway. You may get many years of service with it bypassed. Just check all the other stuff first.


Thanks Gary