Why is my thermostat blank?

Have you ever had a computer malfunction? One of the most jarring situations is a blank screen. You open your laptop to send an email or visit your favorite YouTube channel, but the screen is empty. Something similar can happen with your digital thermostat. But if your thermostat is blank, fixing it might be easier than you think! In most cases, it’s way simpler than dealing with a broken laptop.

Many times, a blank thermostat is something you can fix on your own at home. We’re going to run through all the possible causes of a blank digital thermostat from most common to least likely. By the end, you’ll know everything you need to know about monitoring your thermostat for full functionality moving forward!

Dead batteries

You’ll be happy to know that one of the most common causes of a blank thermostat is one of the simplest fixes. Since a thermostat is mounted on the wall, it might not occur to you that most run on batteries. When the batteries die completely, the screen will go entirely blank. You can push the buttons all you want, but you won’t be able to control the temperature of your home.

If your thermostat is blank and you’re unable to control the temperature of your home, check the batteries first. You should be able to pop the device off your wall. Open the back and take out the batteries. Many thermostats use AA batteries, but double check before buying replacements.

Note that some thermostats will flash a battery icon to indicate low power. This would happen prior to your thermostat going blank, so be on the lookout. If you can catch this warning sign before the thermostat loses all power, you can save yourself some effort. Once a thermostat is blank, it will have lost any energy saving settings. You’ll have to go back in and program your preferences again after you replace the batteries.

Although losing any settings is annoying, replacing dead batteries is an easy fix. You may find that this simple solution gets your HVAC system up and running again. If not, it’s time to keep troubleshooting.

Broken thermostat

Thermostats are designed to last anywhere from 10 to 20 years. They’re one of those devices that you don’t have to think about much. For the most part, they just do their job effectively without any trouble.

But if it’s not the batteries that are dead, then it might be the thermostat. If you’re dealing with a blank thermostat, and you know that your thermostat is on the older side, it might be time to replace it. Checking the batteries should still be your first step, followed by checking the circuit breaker, which we’ll discuss next. But if these both seem to be in order, an old thermostat may just be ready to retire.

A tripped circuit breaker

For most digital thermostats, the batteries serve as a backup power source. Many are hardwired to the home’s electrical system and assigned to a circuit breaker.

The backup batteries are there to protect the thermostat and the HVAC system in the event of a power outage. As mentioned above, losing power will cause a thermostat to lose all of its settings. This is more of an inconvenience than a problem, but it’s still important to keep the batteries fresh.

If a new set of batteries didn’t do the trick, the next step is to check the circuit breaker. A surge may have caused the circuit breaker to trip, which will have cut off power to the thermostat. Head over to your home’s main service panel. This is usually found in the basement or in the utility room. If you see a tripped circuit breaker, give it a flip back on, and check the thermostat.

If this was the cause, and it continues to happen, you may need to call in the professionals. The cause could be related to a malfunction in equipment, or an issue with the wiring.

Wiring problems

A thermostat that continues to go blank due to a tripped circuit breaker might be dealing with wiring issues. This is a circumstance that will require the help of a professional like the Geiler team.

In some cases, the wires connected to the thermostat may be loose. It could be because they weren’t installed properly in the first place, but sometimes they just come loose over time. This is particularly common when the thermostat is set up in a high-traffic area. The continual vibrations from movement in the house can cause the wires to wiggle loose.

Occasionally wires will take on damage from critters. Rodents can chew on the wires and mess up the power. Since checking on the wires requires working with electricity, we recommend leaving this project to a professional.

Tripped safety switch

Many modern HVAC systems are built with a safety switch. Its purpose is to cut off power from the unit should there be a potentially dangerous problem.

For instance, in an air conditioning unit, a safety switch might trip if it notices excessive moisture. By cutting off the power, the switch prevents the A/C unit from leaking excess water into your home.

The safety switch for most A/C units is in the drain pan. If there’s water in the drain pan, it may indicate that there’s a clog in the drain. You could empty the drain pan, flush the drain line, and see if that helps.

When the safety switch on a furnace trips, it’s typically because of overheating. If you’ve gone this far into troubleshooting your blank thermostat without calling in a pro, now might be the time. The fix could be simple, but to ensure things are fixed completely and correctly, it’s good to have experienced help.

Geiler has had decades of experience servicing HVAC systems in the Cincinnati area. Our team will diagnose and fix your home’s heating and cooling system in no time, from the blank thermostat all the way to the overheating furnace.