HI guys, iv'e got a trane xl 80 2 stage gas furnace and trane xe 1100 air condit.the tstat is a trane mod taystat241 . Wired as this-- Y1--yello--W1--white--W2--Blue--G1--green--R--red, The new t-stat is a honewell mod RTH7400. The instr say if my old t-stat had Y1--W1---andW2 --wires to get help! Do I need to research another T-Stat , or can you solve the problem. Thanks again

I don't have the answers, but maybe I can get some ground work in. Sure glad I have somebody to leave the hard ones for. First, click on H&A/C and read the stickies. The W1 and W2 refer to the 2 heat stages. I have a single stage Robertshaw thermostat connected to a 2 stage Bryant furnace. My furnace can either make up its mind which stage to run, or let a 2 stage thermostat decide. I think my W is connected to the W1, and if the furnace thinks it needs stage 2, it fires it up. Yours may work the same way. You may need to dig that info up yourself.