Good morning,

I turned on my old Astra 1 this morning to brew and left it for about 40 min or so to come up to temperature. When I came to make a cup, I heard a hissing noise; The steam wand was passing steam, even though it was fully closed. The needle for the steam pressure gauge had wrapped well past the 2.5 bar limit and was at the 8:00 position of the water pressure side. When I opened the steam valve to release pressure, the steam blast was so violent I closed the valve again. When I operated the brew switch, I was getting almost pure steam out of the group head. I wound up shutting down the machine and vented the steam wand into the tray until the pressure reached a safe level.

On turning the machine back on and observing the operation, the fill pump kicked on, further reducing the water temp and steam pressure. The element came on, and I watched the pressure climb, and then the element kick off at the proper pressure level.

My first guess is the pressure switch, but I also heard from another post that scale could play a part in this. Any thoughts on this?

Concerns: why didn't the PRV vent? Second, It appears that the overtemp switch didn't kick in.

My guess would be a sticking pressure Stat




Randy