Reconnected thermostat doesn't control furnace or AC?

Question

We are doing construction and had to disconnect our (electronic) thermostat. When reconnected, it won't control either the furnace or the AC, that also includes the fan.

I changed out the thermostat, but the new didn't work either. I did a continuity check and the wire is in good shape.

Is there anywhere else to check? A secondary fuse that is tripped? The units' circuits are both on in the circuit box. It seems odd to me that BOTH the furnace and the AC are inoperable.

I saw the weedeater question, but it doesn't seem to be the same issue as it is only the AC involved.

Answer 1

make sure the wires didn't get crossed

Answer 2

make sure the battery in the thermo is charged and inserted correctly next check the main breaker at the panel and if present at the unit also make sure the wiring on the thermo is matched to the unit sometimes installers don't follow the color code- good luck

Answer 3

If you didn't turn the power "off", you might blue a 24Volt fuse by accidentally touching wires.

It looks like a car fuse and it is located in circuit box.

Answer 4

call a pro fore ya do more harm than good