Installation Operation Maintenance

OperationStarting the unit in cooling modeBefore start-up, ensure that allpower cables are tightened.Verify that the unit airflow rate isadjusted according to theinformation provided in the "Supplyfan adjustment" section of thismanual.To start the unit in cooling mode:• Place the zone sensor systemswitch in the "COOL" position.• Position the cooling setpointapproximately 10° below roomtemperature and place the fanswitch in the "AUTO" or "ON"position.• Turn on unit main power supply.The condenser fan motor,compressor and supply fan motorshould operate automatically.There will be a delay of up to5 minutes before the unit starts incooling mode.Operating pressuresAfter the unit has operated incooling mode for a short period oftime, install pressure gauges on thegauge ports of the discharge andsuction line valves.Note: To bypass time delays andverify the operation of this unit fromthe roof, use the "Test procedure"section in this manual. Check thesuction and discharge pressures.Note: Always route refrigeranthoses through the port holeprovided and ensure that thecompressor access panel is in place.Cooling shutdownTo exit the test mode, disconnectunit power for 3-5 seconds andreapply. When running the unitusing the zone sensor as thecontrol, position the selector switchto "OFF".There may be a delay of up to3 minutes before compressors shutdown and an additional one minutebefore the fan shuts down in thissetting.Do not de-energize main powerdisconnect except when unit is tobe serviced. Power is required tokeep the compressor crankcasewarm and boil off refrigerant in theoil (except on units with Scrollcompressors).Final installation checklist• Are all power cables tightened?Check torque of power cablescontact !• Is the condenser fan and indoorblower operating correctly, i.e.correct rotation and withoutundue noise?• Are the compressors operatingcorrectly and has the systembeen checked for leaks?• Have the voltage and runningcurrents been checked todetermine if they are withinlimits?• Have the air discharge grillesbeen adjusted to balance thesystem?• Has the ductwork been checkedfor air leaks and anycondensation?• Has the air temperature risebeen checked?• Has the indoor airflow beenchecked and adjusted ifnecessary?• Has the unit been checked fortubing and sheet metal rattles orany unusual noises?• Are all covers and panels inplace and properly fastened?RT-SVX20B-E455