I am trying to figure out why our heat is not coming on. I am trying to see if I can figure out the problem my process of elimination or if I need to call in a professional. Here is what I have down:

1. I don't think the problem is my thermostat because the a/c works fine.
2. The thermostat clicks when the heat is turned on, but no heat is coming through the vents
3. I checked my furnace (a DuroZone model ed-3) and, according to the guide, the lights indicate second stage heating and that the computer is operating properly.

So here is my question... :confused:

Could it be the furnace filter needs to be replaced? We have lived her 9 months and haven't replaced it (didnt know we needed to... first time homeowners!)

Could it be some switch needs to be turned on?

Could it be the pilot light?

If not, can anyone tell me what they think it might be that I can do... or do I need to call a professional

A dirty filter will keep the unit from working correctly BUT will not stop it from turning on.

The thermostat switch needs to be changed from cool to heat for it to run.

You gave no brand and model number or age of the furnace so it could have a pilot lite but most if not all furnaces of late do not have a standing pilot instead the units have spark or hot surface ignition.

Replace the filter every month or two but looks like you will need to call for ON SITE repair.

You may also look to see if the pilot or ignition has been turned to the off position. If not the case, and you have checked the filter then you should call a contractor.

Could it be the heat is working, but the dampers are not opening to let the air flow. The durozone ed-3 is a zone control board so you apparently have a zoning system for your ductwork. I had the same problem happen to me. Turns out a damper motor went bad.