I don't know if clicking is the best word to describe what it does. The blower is running, after about a few seconds it will make a squeak. After the squeak a few more seconds will go by and it will make a clicking noise then it will whoosh and fire up. It only stays lit for 5 seconds max before quitting and trying again in a few minutes. (also sorry if this isn't in the right category)
1#
2016-06-11
Sounds like a bad thermo couple. Call a repair, quickly, before it gets any colder
3#
2016-06-11
Shutting down after successfully firing up indicates a faulty flame sensor. It doesn't know that it ignited, so it shuts off fuel flow to avoid flooding the furnace with fuel.
4#
2016-06-11
FirstTry turning off the breaker for 5 minutes ... then turn system back on Have the filter/filters been changed recently?
5#
2016-06-11
Soundsl like u have a bad flame sensor or thermocouple as its called in the business
6#
2016-06-11
Call a furnace repair company. The clicking is the spark ignition. The fact that it shuts down after the whoosh suggests an over temperature control issue. I don't think it is actually going over temperature if the fan is running but a sensor might have failed. Don't try to fix it yourself as it is Gas and you don't want to blow up your house.