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It’s one of the scenarios no homeowner wants to encounter: the realization that the air conditioner hasn’t turned on in a while, and the temperature inside has begun to rise. When you arrive at your thermostat to check the temperature, you encounter an even more puzzling sight. Instead of displaying the temperature and system status, your thermostat isn’t functioning anymore. When your thermostat is blank, and the AC is not working, it can leave you feeling at a loss. What are you supposed to do now?

There are several reasons why you might encounter a blank thermostat. Some of them are easy to fix on your own, while others might require intervention from a professional. Use the following guide to explore different potential causes for your thermostat troubles, then identify the right way to address the issue.

Check the Power to the Thermostat and Unit First

Sometimes, the issue is surprisingly simple: the things that need power to function aren’t receiving any. Dead batteries are far and away the most common cause of a blank thermostat. Since the thermostat commands the hardware, a few drained AA or AAA batteries can be all it takes to render your system inoperable. If your thermostat is blank and the AC is not working, first try removing the thermostat from the wall.

Most thermostats will have easily accessible battery compartments on the bank. Replace the old batteries with fresh ones, then reconnect the thermostat onto the wall. It should turn back on and let you control the unit again. However, if nothing happens, you may need to continue your troubleshooting efforts.

Look For Your Breaker Box to Check the Circuit

Locate the circuit breaker for your home to determine whether an electrical overload caused one of the circuits to trip open. Check the circuit that contains the thermostat while also looking at the circuit used by the air conditioner itself. Try cycling the circuits to reset them, then recheck your thermostat. Is everything working again?

If things do begin to work again, you’ve solved your problem — but you should also want to know why the circuit tripped. If the answer is no, there may be another problem. If it happens again, you should contact an HVAC service provider to diagnose the overload and take corrective action.

There’s Faulty Wiring in the Walls

Some thermostats don’t use batteries but instead receive power directly from a connection in the wall. This is especially common with more modern smart thermostat solutions. In some cases, the wiring that supplies these units with electrical power can develop a malfunction. At other times, poor installation practices cause the unit to fail over time. You will need to speak with a licensed electrician or air conditioning technician to diagnose and correct this problem. Never try to make modifications to in-wall wiring on your own.

Your Thermostat Itself May Have Malfunctioned

Like everything, thermostats can and do break. It is possible, especially if you have an older thermostat, that your hardware has simply reached the end of its life. If you cannot get the thermostat to turn back on even after replacing the batteries and checking the circuit breaker, you may need to replace the unit. It is easy to find replacement thermostats in hardware stores, but not all thermostats are the same. If you aren’t sure which is the right one for your needs, ask a professional.

The AC Switched Itself Off As a Safety Precaution

In rare cases, a blank thermostat may signify that the AC unit has turned itself off as a safety precaution. That often happens due to overflowing condensate drain pans or clogged drain lines, causing a floating switch to trip a power cut-off. Not all units that have a tripped safety float switch will also shut off the thermostat. That may be a secondary concern. In either case, you will need extra help to drain the accumulated condensate and prevent the issue from reoccurring.

When Your Thermostat is Blank, and AC Is Not Working, Call a Professional

If the only problem you face is a set of dead batteries, putting your system back into operation should take no time at all. When you can’t locate the problem even after checking power systems and cycling breaker circuits, though, you may need a new thermostat. There is also the potential that something inside your system has developed a fault, too.

When the thermostat is blank, and your AC is not working, don’t sweat it. Call a professional HVAC contractor serving your area today. A pro can assess your concerns, test the thermostat, and provide you with a replacement or a system repair as needed. Although this problem can be a serious source of stress, it’s often an easy fix — so take the right steps today.