Carrier 40QNB018 Installation, Start-up And Service Instructions Manual

Also see for 38BK-018: Owner's manual

Contents

To Clean Outdoor Coil (Outdoor Unit)Some metal parts and sharp fins of outdoor unit coil cancause personal injury during cleaning. Clean coilcarefully.To clean the outdoor coil:1. Remove any dirt or obstruction from discharge opening.2. Use a garden hose to spray water on the coil. Debris thatcollects between coil fins inhibits heat transfer — directthe water spray between coil fins to flush out debris.Cleaning Condensate Drains — Clean all drains anddrain pans at the start of each cooling season. Check the flowby pouring water into the drain.SERVICEWhen servicing unit, turn off all electric power to unitto avoid shock hazard or injury from rotating parts.Do not vent refrigerant to atmosphere when servicingunit. Reclaim refrigerant during system repair or unitremoval.Diagnostic Codes — This unit is equipped with a mi-croprocessor control which continuously monitors the op-eration of the unit. If an operational fault is detected, a faultis indicated by the flashing of the green ‘‘UNIT ON’’ lighton the front of the fan coil unit. A red LED (light-emittingdiode) indicator light, located on the control board in thecontrol box of the indoor unit, will emit a flash code whichcan be used to troubleshoot a system problem. The controlwill continue to monitor the unit and, if the conditions whichcause the fault are cleared, the unit will return to normaloperation. If the fault code is present for 5 cycles of the unit,the unit will be locked out and the alarm is indicated by theflashing of the green ‘‘UNIT ON’’ light on the front of thefan coil unit.To access the LED indicator light, remove the front coverof the unit by removing the 3 screws holding it in place.If the LED indicator light continuously flashes on for onesecond, then off for one second, the control is functioningproperly and no fault is present. A fast flashing LED indi-cates that a fault has been detected. Table 7 lists the numberof quick flashes and the associated fault. If the system doesnot operate, and the LED indicator does not flash, either thepower to the control board is off, or the control board hasfailed.System Tests — System tests listed below are per-formed continuously by the microprocessor. If a fault isindicated, then the system allows only limited operation un-til the problem is resolved. If the problem resolves itself,then the code is cleared and operation resumes.THERMISTOR TESTS — Each thermistor is tested for highlimit out of range (shorted condition) and low limit out ofrange (open condition). If the thermistor is out of range, thefault status indicator comes on and the LED flashes the ap-propriate fault code.Table 7 — System Fault CodesNO. OF QUICKLED FLASHES SYSTEM FAULT2 Room Air Thermistor3 Indoor Coil Thermistor4 Outdoor Coil Thermistor*5 Compressor Malfunction6 Reversing Valve Malfunction*7 Outdoor Air Thermistor*8 Indoor Fan Failure9 Discharge Air ThermistorLED — Light-Emitting Diode*Heat pump systems only.NOTE: If the LED light continuously flashes on for one second, thenoff for one second, the control is functioning properly and no fault ispresent.PRESS SET TIME PRESSTA TAFig. 22 — Setting The Current TimeREMOVE FILTER VACUUM CLEAN RINSE WITH WATERFig. 23 — Air Filter Maintenance14