York YAWS018 - 075 Installation Manual

York YAWS018 - 075 Installation Manual Manual pdf 47 page image

47TroubleshootingShould a major problem develop, refer to the followinginformation for possible causes and corrective steps:Compressor Won’t Run1. The fuse may be blown or the circuit breaker is open.Check electrical circuits and motor windings for shorts orgrounds. Investigate for possible overloading. Replacefuse or reset circuit breakers after the fault is corrected.2. Supply voltage may be too low. Check voltage with avolt meter.3. Remote control system may be faulty. Check aquastatfor correct wiring, setting and calibration. Check 24-volttransformer for burnout.4. Wires may be loose or broken. Replace or tighten.5. The low pressure switch may have tripped due to one ormore of the following:a. Fouled or plugged coaxial heat exchangersb. Low or no water flow (source side heating, loadside cooling)c. Water too cold (source side heating)d. Low refrigerant6. The high pressure switch may have tripped due to oneor more of the following:a. Fouled or plugged coaxial heat exchangerb. Low or no water flow (source side cooling, loadside heating)c. Water too warm (source side cooling)7. Check the capacitor.8. The compressor overload protection may be open. Ifthe compressor dome is extremely hot, the overloadwill not reset until cooled down. If the overload doesnot reset when cool, it may be defective. If so, replacethe compressor.9. The internal winding of the compressor motor may begrounded to the compressor shell. If so, replacethe compressor.10. The compressor winding may be open. Checkcontinuity with an ohm meter. If the winding is open,replace the compressor.Insufficient Cooling or Heating1. Check aquastat for improper location (secondarymode only).2. Check for restriction in water flow.3. Check subcooling for low refrigerant charge.4. The reversing valve may be defective and creating abypass of refrigerant. If the unit will not cool, check thereversing valve coil.5. Check thermal expansion valve for possible restriction ofrefrigerant flow.Noisy Unit Operation1. Check compressor for loosened mounting bolts. Makesure compressor is floating free on its isolator mounts,and shipping bolt is removed from compressor plate.2. Check for tubing contact with the compressor or othersurfaces. Readjust it by bending slightly.3. Check screws on all panels.4. Check for chattering or humming in the contactor orrelays due to low voltage or a defective holding coil.Replace the component.5. Check for proper installation of vibration absorbingmaterial under the unit. Unit must be fully supported,not just on corners.6. Check for abnormally high discharge pressures.AFFINITY SINGLE STAGE HYDRONIC INSTALLATION MANUAL