Based on the information provided, it seems like there might be an issue with the refrigerator's compressor or the refrigerant system. Here are some possible explanations for the problem:
Refrigerant Leak: If there is a refrigerant leak in the system, the compressor will have a hard time maintaining pressure and circulating the refrigerant properly. During the first cycle, the compressor may be able to generate enough pressure to make the condenser coils hot, but as the refrigerant leaks out, the pressure drops, and subsequent cycles may not be able to achieve the same level of heat in the coils.
Compressor Issue: The compressor itself may have a problem. It could be overheating and shutting down or losing efficiency after the initial cycle, preventing it from maintaining the necessary pressure to keep the condenser coils hot.
Faulty Thermostat or Temperature Control: A malfunctioning thermostat or temperature control could cause the compressor to stop running prematurely or too frequently, leading to insufficient heat buildup in the condenser coils.
Blocked Condenser Coils: The condenser coils may be obstructed by dust, debris, or pet hair, reducing their ability to dissipate heat. This can lead to overheating and subsequent shutdown of the compressor.
Faulty Start Relay or Capacitor: The start relay and capacitor help the compressor start smoothly. If either of these components is faulty, it may work during the first cycle but fail during subsequent cycles.
In any case, diagnosing and repairing refrigeration systems can be complex and potentially hazardous due to the involvement of refrigerants. Therefore, it is recommended to have a qualified appliance technician inspect and repair the refrigerator. They have the expertise and tools to safely troubleshoot and resolve the issue, ensuring the refrigerator works efficiently again.