The Andreja Premium has commercial steam and hot water valves. In other words they are non compression and can not be over tightened which results in the destruction of compression type valves. If necessary they can be rebuilt by simply replacing a $3.00 rubber seat. You can see a comparison of the two type here
http://www.chriscoffee.com/faq#18 The newest shipment of Andreja Premiums now are equipped with a larger access panel on the bottom of the machine. We did this because we added a new drain valve that you can attach a piece of silicon tubing to and open with your thumb and first finger to completely drain the boiler. This comes in very handy should you want to store your machine, ship it somewhere, or descale the boiler. We like the fact that we can now completely drain the boiler after bench testing prior to shipping.
The "floats" in the Andreja Premium works as follows. There are two in the tank, the first one is activated when the water level gets close to a point where you must add water. You hear a very low audible beep beep beep nothing else happens. If you continue to use the machine without adding water, after you pull approximately another 5 shots of coffee you will active a second audible alert different from the first. The second is a louder higher pitched constant tone. Contrary to what some people think the machine is NOT rendered unusable when either alert is activated. When the second alert is activated power to the heating circuit is cut but NOT the brew pump. In other words you can finish your shot and then add water.
We have a new vacuum breaker valve
http://www.chriscoffee.com/products/home/parts/vbreakervalve that you can attach a piece of silicon tubing to the top of it and in conjunction with a T
http://www.chriscoffee.com/products/home/isomacparts/brasstconnector you can tape into the exit side of your expansion valve and divert any moisture from the vacuum breaker valve as well as water from the expansion valve back to the drip tray.
Don't forget the Ulka Pump we spec'd for the Andreja Premium has hi temperature cut out in series with the pump to protect it from over heating and burning out.