I inadvertently pulled the chain that operates the fan clean out of the switch! I cannot stop the fan from operating when only wanting to use the light. I replaced 3 speed fan switch with a Westinghouse model #77020. This did not correct the problem. What else can I do?

You may have installed the wrong switch or used the wrong power lead. A lot of switches are wired with different colors and need to be checked with a VOM.