I am the proud owner of a new Andreja Premium. I must say that I love the machine but ... so far I can consistently produce fabulously bitter donut extraction shots and lovely hot milk drinks . With a digital scale and larger frothing pitcher on order I'm sure I will cure all my technique problems eventually.

The question I have is about boiler pressure hunting. The boiler loses pressure very quickly in my opinion. From the time the pressure reaches the top of the band (~1.1 - 1.2 bar) and the heater shuts off, it takes only 3.5 minutes for the pressure to drop to the bottom of the band (~0.75 - 0.8 bar), switching the heater back on. Approximately 15 seconds to "heat" to 1.1 bar then repeat. You can actually watch the pressure gauge drop.

Is this rate of pressure/temperature loss normal?

I expect that a sealed and insulated boiler should hold pressure/temperature way longer. There are no obvious leaks, puddles or steam clouds. I have not made any adjustments to the factory settings.

Further to this, my dead band seem too wide, looking in the little access hole I can see that my Andreja is equipped with a Mater Pressure Stat. Can the dead band be adjusted by the "Home Barista"?

Any information would be greately appreciated.
Thanks, John

JKT wrote:Is this rate of pressure/temperature loss normal?

John,
The dead band on my AP seems to be much tighter, and it cycles even more frequently than yours. I observed that while idle it peaks at 1.2 and takes about 55 seconds to drop to 1.05 before the heating element kicks on again. I'm not sure if the dead band can be adjusted at home, hopefully someone else can chime in and let you know.

Brian

John -

With Anita (CEME pstat), it cycles from ~0.97 to ~1.17 bar and falling pressure takes about 65 seconds. I would agree that your DB seems a little large but, to quote Chris Coffee FAQ:

"Do not adjust the dead band screw (smaller and off-center). A common mistake is to turn it too far and break the pressurestat, which will not be covered under warranty. The deadband factory setting is 0.2 bar; if your machine's setting is markedly greater, call our service department for assistance."

Now true they are talking about a CEME pstat here but I ASSUME the same line of thought would apply to a Mater.

The boiler is, as you say, nicely insulated save for the ends but the majority of the heat loss is to the water in the hx as it performs its thermosyphon function under idle conditions.

Eric S.