The thermostat is your link to controlling your heating and cooling system. The better you program it, the better the comfort level indoors. In spite of everything that you do, there may be a time when you realize that the display on the thermostat is blank. When that happens, you are in for a spin. Thermostat blank does not mean that it is a lost cause now. The could be many reasons why the display has disappeared.
Thermostat Blank – What Does It Mean?
Thermostat blank under usual circumstances means that either the power to it is cut or the batteries have died out. In extreme cases, there is a small possibility that the thermostat has died out on you and needs to be replaced.
Thermostat Blank – Most Probable Causes
Here is the list of most probable causes that can make your thermostat screen go blank.
1. Dead Batteries – If there is no common wire on the wall, the thermostat is mounted on, it means that your thermostat runs on batteries. Quite often, people are not aware that their thermostat needs batteries to power the display screen. Due to ignorance and sometimes due to sheer forgetfulness, they don’t change them until the screen goes completely blank. Typically, the thermostat uses 3-volt lithium batteries or AA alkaline batteries. Best check which ones your thermostat uses before purchasing them in an adequate number.
2. Loose Wiring – The wire with which your thermostat is hooked could be loose. Nothing startling about that. Its a fact and can happen due to a variety of reasons. For example:
1. It was nor attached firmly in the initial stage itself.
2. The rodents have chewed through the wiring.
3. Strong vibrations in the form of heavy traffic or earthquake could have shaken them loose.
4. The children could have pulled the connecting wire accidentally.
No matter what the reason, your HVAC technician can rectify the problem and get your thermostat up and running by fixing the loose wiring.
1. Tripped Circuit Breaker – Loose wires coming in contact with each other can cause a short circuit and trip the circuit breaker. Sometimes even a power surge can do the same. When the circuit breaker trips, it cuts the power supply to the thermostat, causing the screen to go blank. Check the electrical box to see if the circuit breaker has tripped. If it has, flip it back on, and that should sort the thermostat blank problem and light up the screen.
2. Blown Fuse – If everything in the electrical box looks ok, that is, if the circuit breaker has not flipped, there is a slight possibility of the thermostat having blown a fuse. Take out the fuse and check the fuse wire. If it is broken or melted, you need to replace the fuse. However, before replacing the fuse, check with your HVAC technician about the strength and capacity of the fuse that you need to replace it with. Many times the fuse wire is weak and not of appropriate strength to accommodate the power need. Consulting with your HVAC technician will help you buy the best-fit fuse.
3. Screen Resolution Not Sufficiently Bright – The programmable thermostat allows you to fix the display screen brightness. You may have dimmed it and forgotten all about doing so. Else someone else may have done it without telling you. In either case, brightening the screen resolution will make it easy for you to see and read the display. At times, the thermostat may also dim the screen at particular times of day to save power or extend battery life. Again, readjusting the screen settings will take care of the problem.
4. Furnace Door Open – Some thermostats are very sensitive to furnace doors that are left open. It may not always be a possibility, but there is no harm in checking it out. Check your furnace door, if it is, in fact, open or not tightly shut, it may have triggered the screen of the thermostat to blank. Push the door closed and ensure that it is firmly shut. Once that is taken care of, the thermostat should power back on automatically. If the furnace door is not closing properly, you may have to call the HVAC technician to take care of it.
5. Old Thermostat – A thermostat can last anywhere between 10 to 20 years. Unfortunately, you cannot predict how long yours will last. In case your thermostat is more than 10 years old, the probability of it having gone belly up is quite high. However, you need not take our word for it. Ask your local HVAC contractor to come and check it. Based on their recommendation, you can take the necessary action. Our strong advice is to upgrade to a new thermostat if yours is a decade old to avoid futures inconvenience.
Thermostat Blank – What To Do Before Calling A Technician
Before calling the technician, you can do a couple of checks yourself. These will not only help cut down the work of the technician but also resolve the problem of the blank thermostat in case the reason is too fundamental.
1. Change the thermostat batteries to see if they were the cause.
2. Try and change the brightness of the display screen.
3. See that the furnace door is closed properly.
4. See whether the circuit breaker is tripped or the fuse is blown. In this case, you will still have to call the HVAC technician to figure out the reason for the trip or the fuse being blown.
Aztil AC For All Thermostat Problems
The team of Aztil AC often answers to calls related to the thermostat screen blank. Mostly it is one of the above causes that is the source of the problem. The remedial action for some of these can be attempted by the homeowner, but for the other ones, you need the help of a trained HVAC contractor.