Even well-known and trusted thermostats such as the Carrier models can encounter problems. One of the most frustrating problems for a homeowner is when the Carrier thermostat’s screen goes blank. When it happens, the immediate reaction of the homeowner is almost always: “What can I do to rectify the issue?” However, the problem is that many homeowners don’t know whether it is possible to troubleshoot the problem themselves, and if it is possible, they don’t know where to start.
The good news is that homeowners can troubleshoot their Carrier thermostats whose screens have gone blank and can, in most instances, repair the faults themselves. The troubleshooting and reparation procedures are relatively easy for DIY-ers. An HVAC professional is only necessary when the troubleshooting indicates that either the thermostat or another HVAC device is malfunctioning or broken.
In this article, we’ll have a look at the most common reasons why a Carrier thermostat’s screen is blank. We’ll also recommend ways to rectify the issues.
The effect of a blank thermostat
A working thermostat is crucial for an HVAC system to function. If the screen is blank, no communication between the thermostat and the HVAC system can take place.
In other words, a blank thermostat screen means that either all the HVAC devices are not receiving power, or they can still work on their own but can’t be regulated by the thermostat. Also, the homeowner can’t access the thermostat to set it or add and change schedules.
A power cycle might solve the problem
If the thermostat’s circuit breaker hasn’t tripped, it is worthwhile to try and fix the blank screen issue by activating a power cycle. Remember, because the thermostat’s screen is blank, “normal” reset procedures cannot be followed.
To power cycle, the Carrier thermostat, turn off all devices of the HVAC system. Find the thermostat’s circuit breaker and flip the switch to “Off” and wait about 30 seconds. Return the circuit breaker to “On.”
The power cycle might have fixed the problem and the thermostat’s screen will be working again.
Unfortunately, if the thermostat’s screen is still blank, further troubleshooting action has to be taken.
Usually, a blank screen will be fixed after giving attention to the following aspects:
|Aspect||Possible problem||How to rectify – in short||The number of the note below with more detail|
|Circuit breaker serving the thermostat.||The circuit breaker has tripped.||Turn on the circuit breaker.||Note 1|
|Thermostat’s switch.||The thermostat’s switch is not securely on a setting.||Put the switch securely on “heat” or “cool.”||Note 2|
|Batteries.||The batteries are dead.||Replace the batteries.||Note 3|
Note 1: There is no power because of a tripped circuit breaker
The Carrier thermostat’s screen will be blank if the thermostat is not receiving power, and if the circuit breaker which controls the thermostat has tripped, no power will go to the thermostat. To try to fix the problem, turn the circuit breaker on again. (Remember, to turn a tripped circuit breaker on, one must first press the switch down completely and then press it up into the “on” position until a click sound is heard.)
If the thermostat’s screen starts to work after the circuit breaker has been turned on, the issue has been resolved. However, if the circuit breaker trips again, there is a fault in the thermostat itself or one of the other HVAC devices.
To determine whether it is the thermostat that is causing the circuit breaker to trip, check that the circuit breaker is still off and then unplug all the devices which are receiving their power from that circuit breaker, except the thermostat.
If the thermostat’s screen is not blank anymore when the circuit breaker is turned on again, there is no fault with the thermostat. It is another HVAC device causing the circuit breaker to trip and keeping the thermostat’s screen blank. It is recommended that an HVAC technician is then called to find and repair the faulty device.
However, if the circuit breaker trips again when only the thermostat is plugged in, the thermostat is faulty and has to be replaced.
Note 2: The thermostat’s switch is not securely set
If a tripped circuit breaker is not the problem, the next aspect to check is whether the Carrier’s thermostat switch is securely set on either “cool” or “heat.” The thermostat’s screen will stay blank if the switch is not securely set on one of the two possible settings.
The switch could have been unknowingly knocked out of its set position when the area around the thermostat has been cleaned, or if somebody knocked the thermostat when passing it.
To rectify the problem, turn the switch from “cool” to “heat” or vice versa. If the thermostat’s screen is not blank anymore, the problem has been solved. If the screen stays blank, there is a fault with the thermostat, and it has to be replaced.
Note 3: Weak or dead batteries
Some Carrier thermostats use batteries. Dead or very weak batteries cannot provide power to the thermostat, and thus, the screen will stay blank. Check the manual for the type of batteries needed, buy a new set and replace the batteries with new ones. In many instances, this will solve the blank screen problem.
If the Carrier thermostat’s screen stays blank, we recommend that an HVAC specialist is called to verify whether the thermostat has to be replaced.
Even very good thermostats such as the Carrier models can stop working. A blank screen is one of the very frustrating problems that might occur. Although there are various reasons why this is happening, homeowners should be able to troubleshoot the problem and even fix the issues themselves in almost all instances if the procedures and tips given in this article are used.
However, if the screen stays blank after all the steps have been taken, we recommend that a qualified HVAC technician is called upon.
It must be remembered that when the thermostat’s screen is working again, some of the steps which have been taken to rectify the problem might have caused the thermostat to cancel pre-set programs. The thermostat then has to be reset and reprogrammed.
See some good Carrier thermostat models: https://www.carrier.com/residential/en/us/products/thermostats/