Why it matters to you
Pitted, burned or stuck contacts can keep an outdoor unit from starting, or keep it running after the thermostat is satisfied. Fire ants, common across Southeast Texas, are known to nest in outdoor units and lodge between the contacts.
Practical guidance
If the outdoor unit runs while the thermostat is off, or will not start when it calls for cooling, turn the system off at the thermostat and call for service. Contactor testing and replacement involve line voltage and are licensed technician work.