AAON RN Series Installation, Operation & Maintanance Manual

Also see for RN Series: Installation operation & maintenance Installation operation & maintenance Installation operation & maintenance Installation operation & maintenance Installation operation & maintenance

Contents

AAON RN Series Installation, Operation & Maintanance Manual Manual pdf 64 page image

64maintain the setpoint ‘LATset’ to amaximum number of stages set in setpoint‘Stages’.If a safety is reached with the controller’ssafety sensors then the electric preheat willbe de-energized for a period of 2 minutes.Electric preheat will turn on stage one at100% for 3 minutes to test if fault conditionsstill exist after the cool down period. Thecontroller will repeat this and if 3 trips arerecorded in 60 minutes then the controllerwill lockout and require manually cyclingpower to reset.The modulating electric preheat option isdesigned to temper the incoming outside airto the unit based on an enable control signaland the outside air conditions.A 24VAC enable signal must be provided tothe [PHE] terminal to enable the operationof the electric preheat. Once the preheatcontroller is enabled it will monitor theoutside air temperature to determine if anycapacity of preheat is needed. If the outsideair temperature falls below the outside airtemperature setpoint the electric preheat willbe started up and maintain the leaving airtemperature setpoint with both SCRcontrolled and staged electric preheat. Bothsetpoints are set with push button LCDinterface on the preheat controller. Outsideair temperature sensors and preheatdischarge supply air temperature sensors arefactory installed and wired to the preheatcontroller. Electric preheat has maximumoperating outside air temperature of 60°Fand a maximum preheat discharge airtemperature of 80°F.[COM], [PHO] & [PHC] feedback terminalsare provided to communicate if the electricpreheat is in operation. PHO is a normallyopen contact, PHC is a normally closedcontact, and COM is the common. Theseterminals are not required to be connected.[PHE] is the electric preheat operationenable. [PH+] and [PH-] are the preheat setpoint reset terminals.Energy Recovery UnitsGeneral InformationAAONAIRE® units have been equippedwith an energy recovery wheel. This sectionis provided to assure the energy recoveryfeature will be properly setup to perform inaccordance with the job specifications foryour particular application.Energy Recovery WheelThe Energy Recovery Cassette consists of aframe wheel, wheel drive system, andenergy transfer segments. Segments areremovable for cleaning or replacement. Thesegments rotate through counter flowingexhaust and outdoor air supply streamswhere they transfer heat and/or water vaporfrom the warm, moist air stream to thecooler and/or drier air stream.Improper installation, adjustment,alteration, service or maintenancecan cause property damage,personal injury or loss of life. Startupand service must be performed by aFactory Trained Service Technician.WARNING