Why won't my blower come on .My central air and heat unit will not blow out air.the compressor still comes on outside.There is cool air and moisture inside by the furnace and blower.I have changed the thermostat.It still won't blow.It is a Ruud.

According to your recent posts you have been without air conditioning for about eight days due to your furnace fan not operating, I think you should capitulate and call in an expert to solve your problem. Most air conditioning repairmen have acquired their knowledge through special training and years of experience in the field as well as investing thousands of dollars in special tools.
There is no shame in a home owner failing to diagnose their problem, but you have to know when to call in the experts.
Ask your friends who they would recommend and good luck!

It started working but stopped a few days ago.