I recently changed my thermostate and I am getting no power to the new thermostate. I changed nothing wires kept the same as indicated and new thermostate was program as directed. Pleae help

Did you turn the power off to the furnace or air handler first before you messed with the wiring?

It is possible a wire got shorted out during the change over and blew the fuse in the furnace or air handler OR it is possible the low voltage transformer got damaged by the same type of actions.

You will need to track down the circuit or item that is causing the problem and take the corrective measures so your system will be operational again.

If the furnace or air handler has a circuit board the fuse may be located on the board. The transformer will also be located around the same general area.