All of a sudden I have no heat. I have a programmable Simple Comfort 3001 thermostat and haven't had any issue with it for 1.5 years. Forced Hot Air Heat / Gas - what could be wrong ? My furnace has no pilot light - its only 2 yrs old. Help !

You have to give us an idea of what is happening from the time you turn up the thermostat. Does is go through any kind of a cycle or does the blower fan just come on? Give us some hints.

The thermostat stays on auto / heat. It now reads 64 degrees and if I raise the temp I want it to be at the blowers kick in but when I check the return the air is cold, so to answer your question, I think that just the blower fan comes on. I don't know the first thing about this stuff, this is my first house and in case you can't tell... not of the male kind, lol, therefore I'm not doing a good job describing it.

We have talked many inexperience people through such problems. Thanks to Northern Heat, we now have an excellent sticky at the top of the Heating and Air Conditioning. Click on it, and then on the link to Sequence of operations for a gas furnace. It tells what should happen when you turn the heat on. From what you said, it sounds like the upper limit switch is open. If there is a flashing light on the furnace, try to find a pattern to the flashes, a single flash, a pause, 2 flashes is a 12. There may be something on the furnace telling you what a 12 means. Read the sticky, check the furnace, and post back.