Here's the latest....
I cleaned the furnace and also the heat sensor and replaced the fuse. The fan does come on, but the heating element does not come on.
Patrick... I also checked the tube you mentioned. I can activate the diaphragm sucking on it and there is no blockage blowing into the furnace either, so I think that's ok.
I did mention the flashing LED. Found some stuff online at
http://www.diychatroom.com/f17/ (Thanks Trulyvintage) that says to check the polarity if it's blinking steadily, which it is. I'm not quite sure what to do about it though. This error apparently disables the gas until it's fixed so I think I know the problem now. Reverse polarity and I may be back in business.
By the way...6t7gto, you were right. It's a Carrier WeatherMAKER 8000. Sheesh! How blind am I? lol
Here's the manual. It refers to a twinning kit to reverse polarity, but that almost sounds like running two units in tandem or something.
http://www.docs.hvacpartners.com/idc.../58d,u-8sm.pdf
I'm getting closer. Gotta figure out this polarity thing and why it happened after all the time I've had the furncae.
Kevin