MY OLD LENNOX THERMOSTAT HAS 8 LETTERS O-G-Y1-R-L-T-C-W1-.MY NEW HONEYWELL THERMOSTAT HAS 9 LOCATIONS LETTERED RC-R-O/B-Y-G-C-L-E-Aux.WHERE DO I PUT THE L WIRE FROM THE OLD LENNOX THERMOSTAT?

labman

Heating and cooling is not one of our stronger forums. I am guessing this is a heap pump. Since both thermostats had an L terminal, I would assume the wire that went to the L terminal on the old one, would go to the L terminal. If there is more to it, you are going to have to study the instructions for the new thermostat and the heating system. Often a heating system has a schematic on it. Figure out what L terminal on it does, and then find the terminal on the thermostat that fills that function. Sorry I can't give a better answer.