Changed thermostat, not working
I had a new furnace/ac unit installed about three years ago. Always hated the t-stat they supplied with it, was dimly lit and hard to read. Finally had enough of it today and changed it to my old one.
I don't know what brand the one they supplied is, all I can find on it is VT2005. The one I replaced it with is a Honeywell MagicStat/3355. The Vt was a four wire, red, white, yellow, green. I hooked the Honeywell up the same way. Whether it is on heat or air the fan comes on after about ten seconds. The furnace never ignites and the blower keeps running. The air does work, shuts on and off, but the blower keeps running on that also. I do not have it set on constant fan. When the fan was running I switched the switch to system off and it kept running. I then removed all four wires and the fan kept going. I had to go cut the power to the furnace to shut it off. Any ideas? I can not put the VT back on because it got broken during removal. TIA