I moved in my home in July and the AC worked great. I turned the heat on last night and nothing has happened. I followed the instructions to turn on the gas (it never loked like it was turned off). I replaced the thumostat and still nothing. There is a blinking red light on the curcit board when the door switch is pushed in and the power is on. The fan will blow when turned to auto, but air is cold. There is no pilot light due to an auto ignition system. Furnace paper work sayes it is made by goodman manufacturing and no model number on paperwork or furnace that I can see. Any ideas on my problem?

First problem is it is a goodman, second sounds like a wiring or a t-stat problem, did you hook the red wire to rh or rc? Is there a jumper between them?

The replacement T-stat is a honeywell and does not have a yr or yc, just R Y G W ans an O/T. there is no jumper.

Well you can start by turning the power off at the furnace. Then take the t-stat off the wall and put the red a white wires together. Turn the power back on and see if anything happens.

Red and white to which letter post?

No post just to each other off the stat

I put the old t-stat back on. It has the rh and rc post with a jumper between the two. I tried connecting the red and white wires and still nothing.