After three happy months on my second "One" (long story), it is now not building pressure. After 3-4 purges from the steam wand after which the pressure drops to 0, it slowly holds pressure but expels alot of water.
The first time this happened, my milk was milk-water and I was very confused.
After an email to Wendy, she recommended keeping the steam valve open (with a container underneath) until the water becomes steam. I have been doing this, but I can't imagine it is normal for almost a cup of hot water to come out before any semblance of steam.

I have another email out to Wendy but have not heard back.

Any suggestions or am I destined to babysit my "One" for 10 minutes while it warms up?

It sounds like the steam boiler's water level sensor is malfunctioning and overfilling the boiler. With only three month's use, it's hard to imagine scale buildup on the sensor is at fault. Since it's under warranty, I advise against any DIY repairs unless they explicitly instruct you to do so.

How long does the pump auto fill on initial power-on and is the duration different than when you first got the machine?

If I understand this correctly, since the One doesn't have a vacuum breaker valve whatever volume of water is added when cold will need to be purged back out (via the steam wand as it comes to pressure) to return it to the correct level in the boiler.

A ten minute start-up seems short to me.

Not sure what you mean by not holding pressure. Does it build pressure at first and then lose it when you try to texture milk? What is your start up routine when you first power it up?
Ed

MPatrick wrote:If I understand this correctly, since the One doesn't have a vacuum breaker valve whatever volume of water is added when cold will need to be purged back out (via the steam wand as it comes to pressure) to return it to the correct level in the boiler.

I don't follow you. The presence or absence of a vacuum breaker has no bearing on the water level. While Eric's schematic below isn't the Salvatore One, it does demonstrate the point:



The water level sensor is shown on the upper right. It's simply a metal rod used by the autofill circuitry to detect when the water level reaches the bottom of the probe. If it touches the water, ground is present = no need to fill. If it doesn't touch the water, no ground is present = need to run pump until ground is again present.

Sometimes scale buildup can "fool" the sensor by electrically insulating it from the water, thereby overfilling the boiler. A crack in the probe's sleeve can have the opposite effect, i.e., it will always detect ground because it's making direct contact with the boiler. Chris elaborates on this point in FAQ #27 How to properly replace a liquid level sensor probe.

Turn on the machine.
Keep the steam valve closed.
Wait four minutes - or until you hear the pstat's cycling click.
Open the steam valve until pressure drops to near zero.
Close the valve.
Wait 20-30 minutes for full warm-up.
Have at it.

That's the drill.

If you try to bleed the false pressure too soon, you sorta get what Tricie is relating. A bit of a sloppy bleed. Dunno why exactly.

When I first got a One, I would power on and wait for the pressure to rise and hold steady then purge the steam valve and leave it to heat up/rebuild pressure for 15-20 minutes.

Wendy then suggested purging the steam valve of any pressure before powering on and then continuing the warm up process.

Plenty of steam, no issues.

Then last week, it took at least 4 purges or leaving the steam valve open until steam appears (leaving a cup of hot water).
Now that I think of it, I haven't heard the pump activate in a while. I will check again today when I make some espresso.
I have been using Arrowhead bottled spring water. Should I be using filtered tap instead?

Dan,

Thanks for the clarification.

Tricie,

It does sound like it over-filled or is over-filling the boiler. I would try dispensing hot water to the point the pump engages then see if it refills to the correct level (just steam, no water from the steam valve) or over-fills (excess water from the steam valve.)

zoomchick wrote: I have been using Arrowhead bottled spring water. Should I be using filtered tap instead?

Perhaps there isn't enough mineral content to allow the fill sensor to work correctly. Odd if you have been using the same water for a while.

Mark