We purchased our home a year and a half ago and had no problems with our heat last winter. However, when we turned the heat on for the first time this year, nothing happens. We have a Ruud Achiever 90 Plus furnace and I believe it is original to the house, approximately 12 years old. We have tried replacing the filter, reseting the thermostat as well as turning off the furnace, none of which helped. The furnace fan will run when we set the themostat to the fan "on", however, it will only blow out cold air. Is it possibly the pilot light? Any help would be greatly appreciated!

This could be a little complicated but to start I'll need a model number. It'll be inside of the front access cover. It appears that your furnace is of the modulating type and will have no pilot light to blow out.