Hanbell Replacement

Hello everyone,
This is my first post in the forum. I own an ice rink in Greece, so I'm not an engineer. Reason for writing is I would appreciate some help with a problem I am having. I have a water chiller made from a Greek company using Hanbell screw compressors (RC2 260B) with an Alfa Laval evaporator and Air condensers, and Carel controller (Pico 3). A couple of weeks back one of the compressors -we have 2 - blew and the Refrigeration company we bought the chiller from told me it was because our glycol water mixture was too low. We found it was -10 Celsius, we now changed it to -15. We were advised to change the compressor to a Bitzer equivalent because they are better than Hanbell compressors and more efficient in eletricity but will need extra work in installing these as the fittings aren't the same.
Other Ref engineers that I talked to told me that compressors dont break and the first one to break would be the evaporator - not because of glycol mixture- and the problem could be eletrical, oil failure or a combination of other things, same guy also suggested to buy exact same compressor as the chiller is designed with 2 identical compressors, also that the bitzer would be more efficient is a myth, and told me to really save on electricity there's chillers with inverter compressors like Carrier.
Also most engineers advised against using a remanufactured compressor, although I do have a quote -actually I have one from a UK company - though I wouldn't mention it don't know if rules allow it in this forum.
So there's 2 questions really:
What is the reason do you guys think for compressor failure?
Do I use exact same brand new or remanufactured and same time check the whole chiller?
Thank you all for your help
Joseph

If glycol played a part in failure then you would expect the evaporator to be damaged allowing glycol into the fridge circuit, is this the case? It would be money well spent to get a second opinion, find out why the compressor failed and then see what the costs to repair will be, if the root cause of failure is not identified, you may well be replacing a second compressor in a short period of time.

Hanbell is a very good compressor. Humbel uses York on his chillers . Have him and resource more. If you change to Bitzer, you will have to change a lot, including the control system itself. If we are to change, then change the two compressors. Better buy a new chiller. And why such a concentration of low -15 ? Should be 35-40%. Damage to the evaporator of course and at -10 will not, but at a low concentration of ethylene glycol solution more corrosion of steel elements. The compressor could not break because of the low concentration, there is another reason.Do you have ethylene glycol in your compressor? Could be to break the evaporator tubes large flow, but not because of the freezing point of ethylene glycol. Ethylene glycol does not expand like water when frozen.

Hanbell compressors are very reliable. Cheap compare with others but good.

As Al said, glycol can not be the problem, you did not mention how long was the chiller running before that problem occurred.
it a closed glycol/water system so i can imagine the problem is electric.
can you give more details about the electrical and control layout?
A copy of the electric drawings can help.

Thank you all for the replies!
This September when we started making ice that same compressor kept stopping giving alarm - compressor overload . The ref engineer changed the - pardon me I am translating but I m no techie - timer that controls the magnetic valve for loading the compressor. After that the compressor was working again, for about 6 months until it broke. I just talked to him now and insists that my glycol mixture was at fault and caused the compressor to freeze. Just to clarify the chiller is working with only one compressor now with a setpoint at -6.5 Celsius, we have ambient temp around 20-22 Celsius now. I have attached eletrical diagrams.Attachment 15207Attachment 15209Attachment 15210Attachment 15211Attachment 15208

Attachment 15212Attachment 15213

http://www.mcscontrols.com/Documents...e%20Manual.pdf

Compressor overload (motor current overload) - dangerous alarm. A lot of reasons. But the concentration of ethylene glycol in it, could not influence. You need to invite another refrigeration engineer and make a diagnosis of the machine.

Thank you all for your help. I guess I have to do just that, get someone to inspect the whole chiller for faults, before replacing the compressor.
Thanks again