A series of heat pump system simulations are carried out to develop a fault detection method, especially for a system having multi-indoor coils. Five major faults like refrigerant overcharge, undercharge, reduced indoor coil air flow, reduced outdoor ...
A series of heat pump system simulations are carried out to develop a fault detection method, especially for a system having multi-indoor coils. Five major faults like refrigerant overcharge, undercharge, reduced indoor coil air flow, reduced outdoor coil air flow, and superheat control are systematically varied in three distinctive levels. The system behavior is described with evaporation temperature, compressor discharge temperature, saturated condensing temperature, subcooling, indoor air side temperature rise, and outdoor air side temperature drop by imposing individual and simultaneous faults. The multi-fault behavior cannot be explained with individual fault characteristics. Simple fault prediction models are presented for both single and multi-indoor systems, respectively.