Issues with CBus Timer

Does anyone have any idea why this timer won't start? I'm doing my head in haha.

 

This is Pascal, not Python, so indentation does not determine structure (and it doesn't in any sensible language ).
Only the first statement after the IF and ONCE are part of the condition. The other instructions are always executed so you start the timer and then stop it staight away. You need to enclose all the statement that are part of a condition in begin/end blocks.

Also, the first IF MUST be a ONCE

As an aside, there are better ways to do this. Turn the fan on with the light, then pulse it when the light goes off.