I have a Weathertron Thermostat Model # baystat239 and try to convert to Honeywell RTH3100c.

Connecting to weathertron thermostat currently are
x2-black
o-orange
g-green
y-yellow
t-brown
r-red
w-white
b-blue

So the wire I transfer to Honeywell thermostat are
x2-black to E
0-orange
G-Green
Y-Yellow
T-DON'T KNOW
R-Red
w-white to AUX
B-don't know

My question is where I connect the T-Brown wire and the B-blue wire to.
Currently the honeywell L, B, and C is not connected.

My unit is central A/C and heat w/ outside unit -that also have emergency heat if the outside unit is not working.

Thanks

See page 11 and 12.

http://customer.honeywell.com/techlit/pdf/PackedLit/69-1889EF.pdf

Hope this helps.
https://www.askmehelpdesk.com/heating-air-conditioning/heating-cooling-maintenance-repair-troubleshooting-frequently-asked-questions-58313.html#post268211