Canon SPEEDLITE EL-1 Advanced User's Manual page 210

P.Fn-07: (Fan)
You can set whether to operate the fan.
0: ON
1: OFF
Caution
If the fan breaks down or the rpm is high, a warning is displayed and the fan stops.
When shooting a video with the flash connected to the camera, the fan actuation
sound may be recorded.
You can force the fan to stop when P.Fn-07-1 is set.
When P.Fn-07-1 is set, the number of continuous flashes is lower than when the
fan is moving and the required rest time until the warning icon is cleared is
extended.
When P.Fn-07-0 is set, the fan will start when the firing or modeling lamp is lit. The
fan may start even if the flash is not fired depending on the internal temperature of
the flash.
When the fan breaks down, the number of continuous firings (
as when the fan is stopped regardless of the P.Fn-07 setting.
210
) will be the same