What could be a consequence of insufficient refrigerant charge in an HVAC system?

A consequence of insufficient refrigerant charge in an HVAC system is a decreased compressor lifespan. When the refrigerant charge is low, the system struggles to maintain the necessary pressure and temperature conditions to operate efficiently. This causes the compressor to work harder than it should, resulting in increased wear and tear. Over time, this excessive strain can lead to overheating and potential failure of the compressor. Thus, having the correct refrigerant charge is crucial for not only the overall efficiency of the system but also for the longevity of the compressor and the HVAC system as a whole.

The other options do not reflect the implications of insufficient refrigerant charge. Increased energy efficiency would typically be associated with a properly charged system, while improved airflow and reduced thermal resistance are also unlikely outcomes of a low refrigerant condition, which actually tends to hinder performance rather than enhance it.