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Having difficulty setting a thermostat’s mode is not a major predicament, though it can be quite a nuisance in the long run. There may be various reasons your thermostat display is blank, including this generic malfunction.
Power surge or tripped breaker
If the touch screen on your thermostat is blank when you enter your house, it might’ve experienced a power surge. If you have a thermostat that is equipped with an on/off button or a power button, the control panel will pause for a few seconds and then immediately reboot. Other versions of the thermostat may require you reset it by flipping the circuit breaker in the fuse box.
A tripped breaker can cause the thermostat screen to be blank. Try resetting the breaker and allowing the thermostat time to reboot.
A triggered safety switch
High-efficiency systems, heat pumps, and air-conditioners have condensate safety devices to prevent extensive water damage in case of a drain issue.
Gas furnace systems are outfitted with a safety switch which detects if the unit becomes too hot, preventing serious damage.
Any of these safety switch devices could cause the thermostat screen to be blank and your equipment needs to be inspected by a licensed service technician.
Dead batteries
Many residential thermostats are powered by your home’s primary electrical supply.
Some require batteries for proper operation and should be changed at least once a year.
If your thermostat screen is blank and it runs on batteries, replace them.
Open furnace door
Furnace control panels are outfitted with a safety switch.
When the furnace door is removed, the safety is engaged and will shut down the system.
If the furnace door is ajar, or not attached firmly, the safety switch can cause the thermostat to be blank and the system will not engage.
Wiring connection issues
Another cause for a blank thermostat could be simply the thermostat is bad.
You can visually inspect the wiring connections by turning off the power to the thermostat, removing the panel and looking for any burnt wires.
Dust can become trapped inside the panel causing a connectivity issue.
You can use compressed air, sparingly, to remove loose dust.
Reinstall the panel on the thermostat and turn the breaker back on.
If this does not resolve the blank screen, contact your local heating and air-conditioning contractor for a service call.
Thermostat needs to be replaced
Like most electrical components, a thermostat will not last forever.
The average life of most brands is ten-years.
If the screen is blank on your thermostat and is an older version, consult with your HVAC service technician to see if yours needs to be replaced.
Even some of the items mentioned in this article could be a result of an underlying issue.
The best way to ensure your thermostat and equipment are working at optimum levels, schedule a maintenance with your trusted HVAC contractor.
