Short answer
If your AC will not turn on, check cooling mode, the temperature setting, schedule and thermostat batteries if your model uses them. A blank screen can mean lost power or a system safety shutdown. Stop for water, ice, burning smells or repeated breaker trips; leave wiring and electrical tests to a technician.
An AC that never starts needs a different diagnosis from one that runs but blows warm air. A thermostat problem can look like an equipment failure, and a safety shutdown can make the thermostat appear dead. Start with checks that do not require tools or opening electrical compartments.
Find service in your town
Based in Lexington. Select your town for service details and call to confirm coverage.
Monday – Friday, 8:00 AM – 5:00 PM Central Time. Call (737) 260-7255. Appointment availability depends on the schedule and required parts.
Safe Checks Before Calling
Mode and setpoint. Select cooling mode and a temperature below the room reading. Check whether a schedule, hold, vacation setting or screen lock is preventing your change. Consult the model's instructions for any compressor delay; repeatedly switching modes will not speed it up.
Thermostat batteries. If the manual shows a user-accessible battery compartment, replace the batteries as directed. A hardwired thermostat can lose power because of an HVAC problem, so a blank screen does not by itself prove the thermostat needs replacement.
Visible conditions. Note whether indoor airflow starts, whether the outdoor unit responds, and whether you can safely see water or ice. Do not open the disconnect box, remove equipment panels, change control-board fuses or bypass a float switch.
Breaker indication. Note a tripped breaker for the technician. If a breaker trips again after a previous reset, leave it off. Stop immediately for smoke, sparks, burning smells or damaged wiring. Seek emergency assistance if there is an immediate fire hazard.
Thermostat Not Working: Match the Symptom
| Symptom | Possible explanation | Next step |
|---|---|---|
| Blank or dim screen | Battery issue, lost system power or safety shutdown | Check the manual's battery instructions; request service if it stays blank |
| Display works but settings will not change | Lock, schedule or control fault | Review the model's controls; avoid forcing the screen or buttons |
| Cooling is selected but nothing starts | Delay, thermostat signal, power or equipment problem | Record the symptoms for diagnosis |
| AC runs but room stays warm | Airflow, cooling capacity, ducts or sensing problem | Read AC blowing warm air |
| System repeatedly starts and stops | Controls, airflow or equipment problem | Read short cycling |
If the issue is heating rather than cooling, see furnace not turning on or furnace blowing cold air. The thermostat's displayed temperature alone cannot identify which component has failed.
What a Technician Needs to Check
Possible causes include a thermostat or control problem, drain safety shutdown, capacitor, contactor, wiring, power supply or compressor issue. A technician must distinguish them with measurements. Replacing a thermostat on a guess can leave the underlying fault unresolved.
Before a visit, note the equipment model, thermostat model, any error code, when the fault started and what runs when cooling is selected. Keep warranty documents available; coverage, parts and labor depend on the exact model and terms.
Getting AC Help in Central Texas
If indoor temperatures become unsafe, move to a cooler safe location while arranging help. Kimco offers scheduled AC diagnosis and repair, with a flat-rate repair quote after diagnosis. Call (737) 260-7255, Monday–Friday, 8 AM–5 PM, to confirm service coverage and the next available appointment. Kimco does not provide after-hours emergency service.
Manufacturer Reference
Carrier's thermostat troubleshooting guide explains common power and control symptoms and when to stop troubleshooting. Always follow your own thermostat and HVAC manuals; instructions differ by system.
A note on this article
Articles on this site are for informational purposes only. Follow the price scope and sources stated in each guide; published examples are planning guidance, and your written quote determines the installed price. Always follow your equipment's manufacturer documentation for specific procedures. Work involving gas, refrigerant, or 240V electrical systems should be performed by a licensed professional. If you're not sure whether something is safe to attempt yourself, call us at (737) 260-7255.