caravell multideck chiller fault

[han81]

Hi all,
got called to problem with caravell multideck display chiller today. Ran it up and it came down to set temp (4c) ok even with ambient 32c. When compressor stops at set temp it wont come back on when required, instead it alarms with COH. Can anybody tell me what this fault code is? When i turn power off and on compressor comes back on but code still flashes for a while. Model no is SD60/125, refrigerant r404a.
Thanks guys.

[Latte]

32 degrees ambient, no wonder it doesnt work thats way past its design temp.

Dont know this for sure but with what you have got a would hazard a guess of compressor/condenser overheat. Pull the c/u out and you will probably find a probe wedged in the condenser. effectivly its an hp switch using heat instead of pressure. Caravell fit them a lot with their Carel controllers. Will have a dig in the van later, you can change the shutdown temp but without my book i cant tell you the parameter.

Anyway hope this helps

[han81]

Thanks for reply very helpful. Not suprised its a condenser heat fault as manual says they re only designed for an ambient of 25c. If you could let me know how to access the parameters and adjust them it would be a great help as chiller seems to be operational other than this fault. Thanks again