APU fuel purging vent push button

[Shatwa07]

Hi ..
I tried to find any hint / usage for that switch located at the aft bulkhead for apu venting fuel feed lines ?
are there any mechanic used it !

[ampclamp]

It's possible that it is used to run the fuel pump in the event of changing an APU or fuel lines to purge air or preservation fluids. I've not worked on a 320 for many years and don't have the manuals but I think it's along those lines.

[pocker pipty]

[Shatwa07]

Many thanks 🙏