Gas and Oil Home Heating Furnaces - Thermostat Not Working

I needed to move a Honeywell thermostat (oil fired hot water radiant system) a few inches to the right. Should have been an easy job. Now the thermostat does not work (Furnace does not kick on if you crank up the T-stat). I'm 99% sure I got the wires back to their proper locations and they are securely connected. Tried the reset button on the furnace. Is there something else that could have happened? Alternatively are there some things I can do to toubleshoot or work through a process of elimination?
Thanks

Did you turn to power off when moving the thermostat? What happens if you touch the red and white wires?

I have not tried touching the red and white wires, but I did put a meter on them and got no response.

The power was not turned off .

Touching the red and white wires should make the unit turn on. That's what the thermostat does when it calls for heat. If it does turn on then the T-stat is probably bad. If it doesn't turn on then probably the transformer is bad. How is the thermostat connected?

uh...with 3-wires (red, white, yellow)
is that what you mean?

if you didnt turn power off befor changing stat you probably fried transformer or if you have a newerboard you may have only fried the blade fuse on the circit board.To test transformer check for continuity on the high side and the low side of the transformer with the wires disconnected.

You said three wires...do three wires go to the thermostat? Also check the seconary to the transformer 24V I'll bet it's gone...