Possible Duplicate:
Options for adding “C” wire to thermostat

I recently bought the Honeywell THM5320R Wireless thermostat. After going to hook it up I found what many others have, it requires a common wire for power. I looked at some of the other posts on this topic but could use some confirmation.

My HVAC in the attic looks like:

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The items are labeled X R C G W with RCGW going to thermostat. The C connection currently has 2 wires attached, one goes back to the hvac unit itself along with the X wire. The other appears to run to the outside compressor. A second wire from the compressor path (red) is connected to a Blue wire that then runs to the thermostat.

A closer view

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If you look at the thermostat you can see that the blue wire then connects to the yellow terminal (compressor stage 1(?)). I assume that (after looking at the wiring diagram) that this is simply a circuit that powers on the outside compressor.

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So I would assume that to get a common wire (only 4 wires in cable) that I would simply need to run an additional wire from the C terminal on the HVAC to the C terminal on the Thermostat? First I would need to verify 24v.

Does this sound correct?