I am replacing the old mercury thermostat in my house. I have purchased the honeywell 7400. I got no help from their tech support. I have reached the step where it says if you have Y1, W1, and W2 wires call an installer. I also have X1 which is black. I would assume that the X1 would connect to the C terminal for the common. What do I do next? The installer I called was not much help. I also have a X2 wire that was a jumper from the W2 terminal in the old thermostat to a terminal labeled x2 in the old ammano thermostat.

OK
Start over. What wires did you have on the original thermostat, and what terminals were they connected to? You are correct about the X1 most likely being the common terminal (C). And X2 more than likely will go to the E terminal on your new thermostat. Go to the Honeywell website and look at the installation instructions for your thermostat.

Per Honeywell that model is not compatible with my 2 stage heat pump and single stage cooling. X1,Y1,W1,W2,R,G and a jumper wire labeled X2 connected to W2 and a terminal labeled X2.

Those are all connected to terminals labeled the same as the wire. No O or B wire. I have a RiteTemp universal now. Their tech support was no help.

Well Honeywell should know. Who advised you to get that partiular thermostat? A little research goes a long way.