What could cause a thermostat to not cycle a gas heating unit frequently enough?

When a thermostat is set with the heat anticipator too high, it can prolong the amount of time before the gas heating unit cycles on and off. The heat anticipator works by predicting the heating demands based on the current temperature and the desired temperature set on the thermostat. If this setting is too high, the thermostat may determine that the temperature is adequate for a longer period, delaying the activation of the heating unit.

In contrast, if the anticipator is set too low, the thermostat could cycle on and off frequently, causing inefficient operation and increased wear on the heating system. Faulty wiring can lead to erratic behavior, but it would generally cause the system to turn on unpredictably rather than fail to cycle sufficiently. Inadequate insulation in the home can contribute to temperature fluctuations but does not directly affect the thermostat's cycling behavior. Thus, setting the anticipator too high directly prevents adequate cycling of the heating unit.