Stulz CyberCool - Page 48

48
cybercool indoor chiller original instructions
EN/09.2017/G44 © STULZ GmbH – all rights reserved
Compressor
In the compressor there is an ester oil charge, which does not have to be renewed under normal operation
conditionsandholdsoutfortheunit‘slifetime.However,itispossiblethattheesteroil,asitreactshygroscop-
ically, has taken up humidity of the air after repeated recharging of the refrigerant circuit due to repair works.
Theinteractionbetweenesteroilandwaterresultsintheformationofacid.Owingtoahyperacidity,corrosive
processes take place inside the compressor.
•Inthiscaseexchangetheesteroil.
•Checktheoillevelbylookingatthesightglassofthecompressor.
NOTICE
For units with a speed controlled compressor it is not allowed to recharge oil in case of refilling a
refrigeration circuit after a leakage. In such cases exchange the compressor.
Oil level
Duringunitidlenesstheoillevelshouldnotbebelowthelowerquarter(bottomline)andnotriseabovethe
upper line during operation.
Oiltype:BitzerBVC32(factorylling)
•Checktheoillevelattheoilsightglass.
Expansion valve
Therefrigerantcircuitisequippedwithaelectronicexpansionvalve,whichcontrolsthesuperheatinginthe
evaporator.Thesuperheatingisadjustedto5Katthefactoryandmaynotbemodied.Theexpansionvalve
can freeze, if the humidity in the system is excessive.
DANGER
Do not thaw by soldering flame, danger of explosion !
Thawwithmoistwarmcloth.Checkthesightglass.
Green  ok.
Yellow  humidity critical.
Withtoomuchhumidityinthecircuit,theexpansionvalvecanfreeze.Inadditiontothistheesteroilinthe
compressor, which comes in touch with the refrigerant, takes up humidity and loses its ability to lubricate.
•Takeanoilsample,determinethehumiditycontentandexchangetheoilincaseofexcessivehumidity
content.
•Inthiscaseevacuatetherefrigerantcompletelyandrechargeitaccordingtotheabovedescribedevacua-
tion instruction.