The flowchart below shows how a typical gas furnace functions. It may not apply to all furnaces, but many will follow a similar flowchart.
If you are experiencing trouble, you should be able to follow the flowchart and identify at which point your furnace fails. Armed with that information, along with the year, make and model of your furnace, you should be able to increase communications with a service professional, possibly saving you time and money.
To further diagnose the problem, post the information in our forum and we’ll try to offer you further assistance. Again, when posting be sure to include the year, make and model of your furnace, along with any info gained from the flowchart below.
We’ll do our best to offer you good advice, but we take no responsibility if things don’t go right. The best way to repair your furnace is to call a qualified technician.
Operational Sequence Flowchart