Riello NXC 021 - Maintenance Guidelines; Standard Maintenance Recommendations; Maintenance Level 2 Procedures

95
Maintenance
EN
5.1 STANDARD MAINTENANCE
In order to ensure the unit's maximum ef-
ciency
 and reliability, it is recommended to stipula-
te
 a maintenance contract with your local support centre.
The
 contract includesregularinspectionsperformedbythe
service'sexperts,sothatanymalfunctionswillbepromptly
detectedandcorrected,withoutanyseriousconsequences.
With a maintenance contract, our experienced technicians
will beable to ensure thatthe deviceswill last as longas
possible, andthe systemwill be managedin the most ef
-
fectivemanner,evenintermsofcosts.Theair-conditioning
devicesmustbeservicedbyauthorisedprofessionaltechni-
cians,
whileroutinecheckscanbecarriedoutlocallybyspe-
cialised
technicians.
SeetheEN378-4orISO5149standards.
All the refrigerant lling, removal, and discharging opera
-
tionsmust beperformedbyqualiedpersonnel,usingthe
correct materials for the unit in question. Any inadequate
handlingcouldresultinuidleaksoruncontrolledpressure
values.
 Priortoperforminganyinterventionsuponthemachine,
alwaysmakesurethatthepowersupplyisturnedoff.Ifa
coolingcircuitisopened,itmustbecompletelydrained,
relled,andtestedtocheckforanyleaks.Priortoperfor
-
ming
anyoperationsuponacoolingcircuit,theentirere-
frigerant
 charge must be drained from the unit using a
refrigerantrecoveryunit.
Simple preventive maintenance operations can ensure the
unit'sexcellentperformance:
• improvedheatingandcoolingperformance
• reducedenergyconsumption
• preventionofaccidentalcomponentfunctions
• preventionofmajorinterventions,thusensuringsavings
intermsoftimeandcosts
• protection of the environment
Theunitsrequirevedifferentlevelsofmaintenance.
 Any deviations or failure to observe these maintenance
criteria will nullify the unit's warranty conditions, thus
releasingthemanufacturerofanyresponsibility.
5.1.1 Maintenance level 1
Simpleprocedurescanbeperformedbytheuserona
weeklybasis:
• visuallycheckforanytracesofoil(indicationofarefrige
-
rantleak);
• cleantheairheatexchanger;
• checkforanyprotectiondevicesthatmayhavebeenre
-
moved,andanydoorsorcoversthatmaynothavebeen
closedproperly;
• checktheunitalarmreportwhiletheunitisnotinfun
-
ction(refertosection"ControlPanel");
• visuallycheckforanysignsofdeterioration;
• checkthechargeonthelevelindicator;
• checkthat thedifferencein watertemperature between
theheatexchanger'sintakeanddeliveryiscorrect.
5.1.2 Maintenance level 2
This level requires a specic know-how in the electrical,
hydronic,andmechanicalelds.
Thismaintenancelevelcanbeperformedmonthlyoryearly
accordingtothetypeofverication.
Under these conditions, it is recommendedto perform the
followingmaintenanceinterventions.
Performallthelevel1operations,andthenperformthefol-
lowing:
Elect
ricalchecks
• Tightenthepowercircuit'selectricalconnectionsatleast
onceayear(seethetablecontainingthetighteningtor
-
ques).
•
 Ifnecessary,checkandtightenalltheconnectionsforthe
controls/commands (the table containing the tightening
torques).
• Dustandcleantheinsideofthecontrolunits,ifnecessary.
• Checkthestatusofthecontactors,switches,andcapaci
-
tors.
•
 Verifythepresenceandchecktheconditionsoftheelec-
trical
protectiondevices.
• Checkthatalltheelectricheatersarefunctioningproperly.
• Checkthatnowaterhaspenetratedintothecontrolunit.
Mechanicalchecks
• Checkthetightnessofthefasteningboltsofthefanco
-
lumn,
thefan,thecompressor,andthecontrolunit.
Watercircuitchecks
• Alwaysusecautionwhenworkingonthewatercircuit,and
takecaretoavoiddamagingtheadjacentcapacitor.
• Checkthewaterconnections.
• Check whether the expansion tank shows any signs of
excessivecorrosionorgasleaks,andreplaceitifnecessa
-
ry.
•
 Draintheimpuritiesfromthewatercircuit.
• Cleantheimpuritiesfromthewaterlter.
• Checkthexedspeed pump's bearingafter17,500 hours
ofoperationwithwater, andthesealofthe mechanical
pumpafter15,000hours.• Check theoperation ofthe
lowwaterowsafetydevice.
•
 Checkthestatusofthepipes'thermalinsulation.
• Checktheconcentrationoftheanti-freezesolution(ethyle-
ne
glycolorpropyleneglycol).
Cooling circuit
• Thoroughlycleantheairheatexchangerswithalowpres
-
surejetandabiodegradabledetergent.
• Checktheunit'soperatingparametersandcomparethem
withthepreviousvalues.
• Perform an oil contamination test. • Change the oil if
necessary.
• Checktheoperationofthehigh-pressureswitch.Replace
itiffaulty.
• Checkthecleanlinessofthedehydrationlter.Replaceitif
necessary.
• Keepandmaintainamaintenancesheetforeachunit.
Alltheseoperationsrequiretheusertostrictlyfollow the
safety measures: personal protective equipment, com-
pliance
 with all sector regulations, compliance with all
applicablelocalregulationsanduseofcommonsense.
5.1.3 Maintenance level 3
Maintenanceatthislevelrequiresspecicskills,permissions,
instrumentsandknow-how,andtherelativeoperationsmay
onlybecarriedoutbythemanufacturer,itsrepresentatives,
or other authorised agents. These maintenance operations
involvethefollowinginterventions,forexample:
• thereplacementofmajorcomponents(compressor,eva-
porator,
etc.);
• any interventions upon the cooling circuit (handling of
therefrigerant);