Which factor can lead to thermostat erratic behavior in controlled heating?

Thermostat erratic behavior in controlled heating can often occur due to dust accumulation on the contacts. Dust and debris can hinder the proper functioning of the thermostat by interfering with the electrical contacts that control the heating mechanism. When dust builds up, it can create resistance or lead to intermittent contact, causing the thermostat to behave erratically—turning on and off unpredictably or failing to maintain the desired temperature.

This problem is particularly notable in environments where cooking equipment is used, as grease and food particles can contribute to dust accumulation. Regular cleaning and maintenance are essential to ensure the contacts remain free of contaminants, allowing for accurate readings and reliable operation of the heating system.

Other factors, while they might affect the overall operation of a thermostat or temperature control system, do not directly cause the erratic behavior associated with dust accumulation. For instance, low battery voltage may lead to power issues, incorrect sensor placement may cause inaccurate temperature readings, and full expansion of the bellows could affect mechanical response but would not directly disrupt the electrical connections in the same way that dust does.