Hey all,

Starting yesterday, my NS Oscar started thinking it had no water even though the reservoir was quite full. I have a vacuum breaker on this machine, so I don't have to equalize by leaving the valve open, but that's what did the trick yesterday: unplug machine, come back an hour-ish later, replug, start machine, wait 5 minutes, open steam, shots pull GREAT. Problem is that the ailment occurred today as well...any ideas?

I don't have an Oscar, but I have a machine with a water-level alarm. The alarm sounds when the water in the reservoir drops below to metal contacts. The metal contacts carry an electrical current when water is in the tank. If one of the wires connected to the contacts comes loose, the alarm will sound.

Here is a picture of mine (see the two wires?):

HB wrote:I don't know the particulars of your espresso machine, but I would guess that it has a weighted switch under the tank that must be pressed down to register "water available." Maybe it is sticking or one of the wires has come loose. Unplug it and take a look...

Dan,

There doesn't seem to be any switch, but there are 2 lines that feed into the tank entry point that would indicate low water. I know the tank is flowing free because of the gurgle I get when I plug it back in. I suppose I could remove the screws and make sure the connection is OK.

I had the machine top open when I posted this, just in case anyone knew I could just take a look.

Any chance that some distilled water got into the reservoir? If the water doesn't have enough mineral content it won't conduct electricity and the reservoir will register empty.

And to further provide more data as to a possible cause: yesterday when I got it working, the machine would pull shots and, as soon as I killed the pump, the low water light would kick on. This was instantly remedied by turning the machine on and off.

Based on suggestions, I checked to see if there was any sort of pressure switch for water level. Instead, I found a nub to penetrate the bottom of the water tank, along with 2 wires running to the neck surrounding said nub. They were screwed against the neck, so perhaps the feedback is once the water gets below those screws? I unscrewed and rescrewed, making sure they were extra tight. The "solution" from yesterday is still occurring, which is annoying but allows me to pull shots.

JB130 wrote:Any chance that some distilled water got into the reservoir? If the water doesn't have enough mineral content it won't conduct electricity and the reservoir will register empty.

I get my water from my job, where we have an on site "everything under the sun" filtration system. That might remove enough minerals to keep the screws from registering full. Maybe mix 50/50 with tap so the solids are low but there's enough minerals to keep the thing registering.

JB130 wrote:Any chance that some distilled water got into the reservoir? If the water doesn't have enough mineral content it won't conduct electricity and the reservoir will register empty.

Most likely. Here in Norway we must wire away the "empty tank" indicator because of our water. Without any mineral content it will display empty tank. Putting salt in your water will resolve it (but not taste good), changing type of water may help, if not you can connect the two wires together.

hey, i have exactly the same problem, and have figured out how to fix it. the problem happens (for me) when the water reservoir is removed, introducing an air bubble between those conductivity sensor screws. when the reservoir is returned, there is too much head pressure from the water in the tank to allow those bubbles to escape. i solved it (just this morning actually) by pulling the reservoir up slightly (not enough to break the o-ring seal between it and the inlet, and pushing it back down with a little extra force, thereby forcing the air bubbles out the one way valve. it took about three of these "re-seatings" to get the light to register water again.

in my case, i don't get this problem unless i remove the water tank and replace it. hope this helps.

-mike

This worked for me. Thanks for the advice. I had to lift and reseat it about 6 times, the "gurgling" noise stopped, and it worked.
After that, I need an espresso!