Trying to wire up a Honeywell RTH2410 and Ive got 8 wires.
R, T, O, G, Y, X2, B and W.
Im not clear on the T, and X2. It says to tape off B, and run X2 into Aux terminal with W. No mention of T wire (Brown).
Should I tape off both T and B? Also, should I combine X2 and W into the Aux terminal?
Thanks,
Steve

What do you have available on your new stat?

See: Thermostat wiring colors and furnace terminal designations repair. (http://www.toad.net/~jsmeenen/wiring.html)

O/B, Y, R, G and W/AUX

Bet you have a Trane system.
B is likely common, since using O and B is usually done with some zoning systems.
"T" you will have to tape off.

You have the wrong stat. You need something with 2 stage heating where the second stage is emergency/aux heat.