Measuring from the 4 stubs that look like table-top feet, on up to the tops of the cartridge covers, it look like about 26" at least. Just eyeballing it I don't think I see much hope of being able to maneuver it through a 24" door, even rotated 90 degree on its length and turned at an angle. I rolled mine in on its stand through a 32" door with no trouble.
You certainly wouldn't want to remove the cartridge assemblies, but there might be some way to take off the feet at the bottom which would probably put you at about 24". It's hard to tell, with the stand on I can't see all of the "foot" assembly so I don't know what it might take to remove it. Maybe you could find an exploded part view online.
You might be able to open that door up a little temporarily removing the wood moulding on either side.