Expobar Office Control cools after first pulls

Equipment doesn't work? Troubleshooting? If you're handy, members can help.

#1: Post by paulpegg »

My Expobar Office Control is about 15 years old. I replaced the relief valve a few years ago. Otherwise it is original. It is lightly used with a double espresso and two cups from the hot water wand each day. Starting temperature is about 210F. The pump runs after the second pull from the wand so the boiler should be full.
Lately I have found that the water wand will not run if the machine has been idle for a while. I can still run the pump from the espresso buttons but the water is cool, about 150F. I never use the steam wand but it works fine when testing at startup.
Is this the pressure stat or the thermostat that is not resetting after the initial pulls?
Any other thoughts?

Team HB

#2: Post by JRising »

Yes, maybe...
Something, perhaps the pressostat, is getting too hot and failing. You're going to want to run the machine with the top off so that when you catch it happening you can check voltage at various components.

It's not likely to be one of the safety thermostats, because they don't normally reset themselves, but don't rule them out. Worst case scenario would be a problem on the powerboard, either that the relay on the powerboard fails when hot or the transformer's output drops below the threshold needed to keep things alive.

Don't work in or on a live machine if you're not sure what you're doing and how the multimeter works.
I'd advise leaving the multimeter by the machine with one lead in an easy to access neutral connection, then when the machine fails, start checking the components, element, safety t-stat, p-stat, etc. back toward the powerboard.

(Note: I don't know the Expobars at all, except for the obvious fact that all E61 clones are so similar).

Team HB

#3: Post by ira »

It could be the pressure stat or it could be the Gicar box failing when warm if as I suspect power is removed from the heating element when the water is low. The water spout is fed by the pressure in the boiler and will not work if the temperature is cool. If you measure the voltage across the pressure stat when the machine is cool, it should be 0V, if it 117V or so then the pressure stat is failing, if it's 0V then it's more likely the Gicar is failing. You can also check the voltage across the safety thermostat which should always be 0V, anything else would imply it's been triggered and causing a problem.

paulpegg (original poster)

#4: Post by paulpegg (original poster) »

Thanks to both ofd you. I will start checking those voltages.

I noticed last night after the machine had been on all day that all 6 lights over the buttons were blinking and would not respond to attemptes to turn them off . I cycled the power and they came back off and I pulled hot water from the wand.