I don't know the code for timer, but you can try 256 possibilities by using
IrScrutinizer to generate Pronto Hex.
Add the following text:
[protocol]
name=Dysan
irp={38.0k,780,msb}<1,-1|1,-2>(3,-1,D:7,F:8,1,-100m)+ [D:0..127,F:0..255]
to irpprotocols.ini, start IrScrutinizer and use the Generate tab. Enter 80 into the D box and any number between 0 and 255 in the F box.
To generate a file of all 256 signals, enter * into the F box, and click Export. Just click cancel to dialogs like "manufacturer", etc, but do provide a file name.
By the way, the AM04 fan uses device 72 rather than 80.