So. I am a carpenter by trade. My family is masons. Know the other trades, blah, blah, blah. the one trade Im useless at is hvac. so I made a custom barn door for someone and it was to hide things on her wall. one of those things was a thermostat. it stuck out of the wall so I replaced it with a smaller thinner Honeywell. hooked up the g the y the o and the r which is bridged to both r's. the old one had the black wire hooked up to the x but the new one said to bury it. "tested" it. the fan blew for both heat and a/c, the a/c worked, but got a phone call that the heat wasn't working. btw. it is a trane heat pump/ air handler in a condo. so I went there today and turned off the circuit and the switch that was wired onto the unit. I put the black wire to the b and turned everything on. nothing happened. turned everything off. dissconnected the black turned it back on. nothing happened. looked for the small amp fuse and I couldn't find one. so I crossed the g wire with the r wire and the fan didn't turn on. I'm guessing no power. the thermostat still was clicking but nothing was turning on. How bad did I screw things up?