It is very easy to replace the unit: just remove the T-disc holder by spreading the plastic clips on the sides and pulling it up and out, then push straight up on the beverage outlet (where the drink comes out to fall into the cup). If you haven't had it out for a while, it may stick a little bit, but keep at it, wiggling and pushing and it will come out. I just spent an hour cleaning my old one, as it was full of old grounds/leaves that had cooked into the unit and it was a mess. The small holes that the steam goes through were plugged, and the steam and water were coming out the sides of the unit. I got it clean, but for the time and the mess, I would have gladly paid the ten bucks, popped the new unit in, trashed the old one, and been on my way to a good cup of brew. You can clean the old one and save a few bucks, but it took a pocketknife, a matchstick, a piece of stiff but thin wire, and a stiff brush to get it done for me. God knows what was growing in there; clean early and often with the little green cleaner disc and the dishwasher, then pull the whole works apart and replace the piercing unit. That's really where the gorp is living, and the descaling solution won't help that. The solution only works on the scale left by hard water, and doesn't really clean the machine of the grounds and stuff.