Password for mounting disk in Disk Utility Recovery mode?

I have a 2012 MBA, with an SSD which is encrypted with Filevault. However, when running Disk Utility to check the disk in OS X, an error is found, and I am instructed to run Disk Utility from the Recovery Disk (CMD+R during startup).

Because the disk is encrypted, I have to mount it in Disk Utility in order to gain access to it and subsequently fix it. However, Disk Utility asks me for a password to mount said drive. I have no clue what this password is. It is certainly not my admin password.

I tried using the Filevault recovery key to unlock it, but to no avail. I could disable Filevault encryption and gain access that way, but optimally I would like to resolve the password issue. Is there any way to change this password? I have yet to find a setting for this in OS X (though this might be due to retardation on my part).

Did I screw up the password, or is there some other factor at large here? Any help would be greatly appreciated!

Thanks!

I must have changed something, because my admin password does not unlock (or mount) the drive in Disk Utility.

Could it be that I created a separate password for FV during setup? I cannot for the life of me remember if that was the case (or if thats even possible. In such an event, I didn't jolt it down in 1Password for safe keeping..

I guess I'll have to disable/enable FV again and pay close attention.

Thanks Weaselboy, helpful as always!

Ok, so changing my admin password to something else, resolved it. It does not explain why my former admin password didn't work, though. Glitchy.