new and old
customer has and 1984 mastertrol mark v mabs-V-3 zone control panel that was working fine till he replaced the t stats with a LUX2900 programmable (3 t stats )3 zone , and they have 3 wires, I don`t think you can make the new programmable t stat work in place of the old round Honeywell (57?) any ideas , thanks, tom gray grayequuipment hvac services , email@example.com ps only 3 wires in the wall, If there were 4 wires I think I could make it work,65 yr old tech
I agree with you that if you had a extra wire for the common you could get it to work. Have you thought about using a Venstar add a wire to each zone?