Check the request at the thermostat
Confirm that the thermostat is calling for cooling, and check whether a schedule or hold has changed your intended setting. Note the displayed room temperature. If the system has just been turned on, give it the normal operating time described in its instructions rather than repeatedly switching modes. Tell the technician whether the problem began suddenly or developed gradually.
Gather details without opening equipment
Does the problem affect the whole house or one room? Are accessible indoor registers blocked by furniture? Is there visible ice or water around the equipment? Observe from a safe position without reaching into the outdoor unit or removing covers. A photo of a visible symptom can help explain the issue, but it does not establish the cause.
Leave the repair to a qualified technician
Cooling problems can involve airflow, controls, electrical components or refrigerant. Do not chip off ice, attach gauges, add refrigerant or open electrical compartments. If you notice ice, turn cooling off using the normal thermostat control and arrange service. For smoke, sparking or immediate danger, stay clear and contact emergency help. Call Comfort Nest with the model and symptoms to discuss next steps.