7 System configurationInstaller and user reference guide21VAM350~2000J7VEBHeat reclaim ventilation unit4P487293-1A – 2018.05NOR. H M NOR. H MSS1 SS1qabecdfghijklmnopX20AX21AX41AX42AX38AX14AX33AX35A X70A X24A X26A X28A X22A X29AX5A X6A X12A X11A J3 J2 J1 JC F2 F1 N/P2 P/P1J3 J2 J1 JC F2 F1 P2 P1X27AF1U 6.3AL Na Power supplyb Terminalsc Damperd Damper (only models 1500+2000 bottom unit)e External damper (field supply)f Fan communicationsg KRP2A51 (option)h Controlleri Central controlj External inputk Outdoor air thermistorl Indoor air thermistorm Damper (only models 1500+2000 bottom unit)n Dampero BRP4A50A (optional accessory)p CO₂ sensorq Factory setting (No operation if setting is changed)NOTICEFactory settings: Do NOT change the switch settings whena controller is connected. SS1 is a setting switch to operatethe unit without controller. Changing the switch settingwhen a controller is connected will stop the unit fromoperating normally. Keep the switch on the PCB in thefactory setting position.6.5.5 Guidelines when connecting the electricalwiringKeep the following in mind:▪ If stranded conductor wires are used, install a round crimp-styleterminal on the end of the wire. Place the round crimp-styleterminal on the wire up to the covered part and fasten the terminalwith the appropriate tool.b aa Stranded conductor wireb Round crimp-style terminal▪ Use the following methods for installing wires:Wire type Installation methodSingle-core wirec bcaaA AA´A´a Curled single-core wireb Screwc Flat washerStranded conductorwire with roundcrimp-style terminalc b ba caBBa Terminalb Screwc Flat washerO AllowedX NOT allowed7 System configuration7.1 About control systemsControllerPurposes and applications Description of the system CentralcontrollerUnified ON/OFF controllerSchedule timer Controller forheat reclaimventilation unitController forair conditionerOperation/stopIndependent system control systemBasic method to operate the heat reclaim ventilationunit— — — ◯ ◯ ◯