How do you check a thermostat fuse?

Simply locate your breaker panel or fuse box (usually either outside your home or located in a closet somewhere inside) and look for the fuse or circuit that your furnace is on. If the fuse is blown, replace it.

Why is there no power to the thermostat?

However, if the breaker trips a second time, you might want to contact a professional unless you have experience in this area. Another reason why there’s no power to the thermostat could be due to a bad transformer or even a faulty wire running from the thermostat to the transformer.

How are the controls on a thermostat powered?

On the other hand, the display and the controls on some thermostats are not powered by batteries. In fact, many thermostats are powered by the 24 volts from the transformer. This transformer is located inside your HVAC equipment. This is what is referred to power stealing technology.

What does it mean when your thermostat goes blank?

This is what is referred to power stealing technology. However, if your HVAC equipment has low voltage, it can cause the screen on your thermostat to go completely blank. When you find yourself in this position, again check your fuse box to make sure you didn’t trip a breaker. If you find that you did trip a breaker, simply reset it.

How can I tell if my thermostat is wired to the Control Board?

Another thing you’ll want to check is to see if your thermostat is wired correctly into the control board. On your control board, you’ll find several terminals that your thermostat will need to be correctly wired into. On your circuit board, you’ll find a R terminal, a C terminal a G terminal, a Y terminal, a W terminal.

What to do when you have no power to your thermostat?

Like mentioned already, when you have no power to your thermostat, there are several reasons why this could be happening. For your convenience, use this simply checklist: Inspect the breaker box to see if a breaker has been tripped. If so, reset it.

Why is my thermostat not connecting to my furnace?

If your previous thermostat did not use a C wire, it’s unlikely that it is connected at the equipment. Verify the C wire is connected to the C terminal in your furnace or air handler. Check your jumper selector switch.

Why does my thermostat go blank when I turn it on?

Even if there is still some power in the batteries, dying batteries could result in intermittent power to your thermostat. So if your thermostat goes blank and then comes back on, try putting in fresh batteries and seeing if that fixes your issue.

How can I tell if my ceiling light is hot?

Contact the center of the socket with one of the meter’s probes and touch the side of the socket with the other. If power is present, the meter will light up or vibrate to alert you that it is hot.