Safety & CodesQuestion 107 of 110
A furnace's high-limit (temperature limit) switch protects the equipment by doing what?
a.Metering gas continuously
b.Shutting off the burners if the furnace overheats
c.Increasing blower speed permanently
d.Recovering refrigerant
Explanation
The high-limit switch senses excessive heat exchanger temperature, typically from low airflow, and shuts off the burners to prevent overheating and fire. Repeated tripping signals an airflow problem such as a dirty filter or failing blower. It is a key safety control that must never be bypassed.
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