What may occur if voltage to a single-phase sealed compressor is too low or high?

When voltage to a single-phase sealed compressor is either too low or too high, it can lead to a situation where the compressor draws more current than it is designed to handle. This increased current can cause excessive heat to build up within the motor. If the motor continues to operate in this state, it may surpass its thermal limits, leading to tripping on overload protection. The overload protection is a safeguard designed to prevent damage to the motor by shutting it down when it senses that the current draw is too high, indicating a potential failure or excessive heat condition.

In the context of air conditioning and refrigeration systems, maintaining proper voltage levels is crucial for efficient operation. A well-balanced voltage supply ensures that the compressor can function optimally, protecting both the motor and the overall system integrity.

The other options do not accurately reflect the consequences of improper voltage. For instance, having no effect would disregard the critical nature of voltage on motor function, while a locked motor condition pertains more to mechanical issues rather than voltage irregularities. Similarly, suggesting that the motor would run slightly cooler incorrectly implies a positive effect of voltage issues, which is not the case.