Had my Lennox G61MPV installed and an Aprilaire model 8366 2 stage stat. I heard one of the installers tell the other that I only had 4 wires coming from the stat to the furnace and the new furnace required 5 but he said he'll just jump one of the wires so it will work.
I didn't question it then but I am now since it seems like the furance only runs in one speed, high. The manuals from both the furnace and stat show they need 5 wires and I actuall called Aprilaire who confirmed what I was reading.
Can you please tell me what is the correct number of wires needed and if this jumper they put in actually allows the furnace and stat to work correctly.
Thanks for your thoughts!