Teardowns I've Worked On

Guides I've Contributed To

Completed Guides


  • Answer to: Brew light off before shot completion.

    This does not indicate a problem with the machine. The green light turns on (and the heating element turns off) when the boiler has reached brew temp (127C/260F). When you press the brew button, the pump turns on and pressurizes the system enough to push hot water out of the boiler and through the portafilter, at the same time drawing room-temperature water from the tank to replenish the boiler. As you might imagine, this has the effect of gradually lowering the boiler temperature until the lower-limit thermostat trips (95C/203F), turning the ready light off and the heating element back on. The temperature of the boiler will constantly bounce between these temperatures any time it's on; running the pump simply speeds up the trip across the range. I hope that isn't too confusing, in short, your machine is working as designed :)
  • Answer to: no water out the brewhead

    When you say brewhead you mean without the portafilter in place, correct? If the water flow from the wand is fine then there probably is a blockage in the brewhead passage; if so it's most likely to be calcium and you might be able to fix the issue by descaling the machine. If this doesn't help then removing the screen, boiler screw and spring/valve assembly should allow you to inspect and clear whatever the blockage is. If the flow from the wand is poor then you could be looking at a larger calcium buildup or a failing pump. I would still run a descale cycle first before purchasing a new pump.
  • Answer to: Machine is losing presure while steaming milk

    Make sure you start with a full boiler by first running water through the steam wand before switching to steam mode; since the pump doesn't run when steaming you only have what's already in the boiler to work with. If this doesn't help, you may need to descale the machine as mineral buildup on the heating element inside the boiler can reduce it's ability to heat to the proper temperature as well as recover quickly once temperature drops.
  • Answer to: All appears normal except when the portafilla arm is attached

    Hi Paul, The most common cause of these symptoms is a clogged portafilter basket. Take your basket out of the portafilter handle and hold it up to a light; you should be able to see through the majority of the grid of tiny holes in the bottom. If you can't, apply some citrus cleaner or other similar detergent to the bottom of the basket and and work it over with a wire brush. Once you've got most of the holes unplugged, try your shot again. If your basket isn't plugged, try running a shot through with the portafilter and basket in place, but with no coffee in it. If water still doesn't come out, then your portafilter might be clogged or broken inside, and you'll need to disassemble it to find out. This guide should help you with that: Repairing Starbucks Barista Portafilter If water comes through the portafilter when it's empty then there's a slim chance the problem is that your espresso is ground too finely, or you're putting too much in the basket. Try grinding it coarser, fill it only to the top and don't ...
  • Answer to: On light is on. No Ready light. Pump not working

    If the machine is not heating (does the top feel warm at all?) then it's likely that you've either tripped the fusible link (protects against overheating), one of your thermostats is faulty or your heating element has ruptured and failed. You can check all of these with a voltmeter, but you'll need to take the top of the machine off first. Make sure the machine is unplugged, then check for continuity across each of aforementioned parts; they should all be closed. If any of them are open, or have no continuity, then that's your faulty part.
  • Answer to: The portafilter when attached to the machine blows out coffee

    The most likely cause of this is either an old brew head gasket that is no longer forming enough of a seal or the small plastic ramps inside the brewhead are broken or missing.; they press the portafilter up against the brew head as you rotate it. It's also possible that your basket or portafilter is clogged and/or your coffee is ground to fine, but on a properly operating machine this would not result in the blowout you're experiencing. When you attach the portafilter, does it easily turn all the way to the right or is there some resistance? Try to brew with no coffee in the basket; do you still get the blowout effect or does the water dispense through the spouts as it should?
  • Answer to: Why is there no flow through the portafilter?

    Does water flow through the portafilter with no coffee in it? If so, it could be that your coffee is ground too fine or tamped too hard (if you're tamping at all). There's a chance that your pump is failing but this is very rare.
  • Answer to: Pressing the power button starts the pump.

    It sounds like you didn't correctly reinstall the steam knob. When turned it should activate a switch, turning on the pump, but it should not be activating the pump in it's resting / off position. You'll need to take the top off again and readjust the position of the knob on the shaft via the hex head nut.
  • Answer to: Runs when the steam or expresso option not pressed

    Hi Dick, make sure your hot water / steam knob is closed as tightly as possible. If this is opened just a little bit then it will activate the pump. If the knob has slipped out of position and is activating the switch no matter what you'll need to take the top off of the machine and reposition the knob on the valve via the hex nut on it's shaft.
  • Answer to: Brew head leaking - brew button problems - Wand working?

    Is your pump running as soon as you turn the machine on? Check that your steam knob is closed all the way.


  • Starbucks Barista Teardown

    Actually, the link is not working at all, which isn't surprising given that the comment is nearly 4 years old. Here's an updated link to the wiring schematic:


    If and when that link stops working, you should be able to find all the Barista diagrams and manuals here:


  • Starbucks Barista Teardown

    They do not, they only control the heating element and what temperature it's at. The one thermal breaker in the machine is a fusible-link type, so when that trips it has to be replaced. Any chance you have the machine plugged into a GFCI outlet and is that is what's clicking off and back on again?

  • Starbucks Barista Teardown

    Edie, that part should unscrew from the bottom of the boiler; taking the boiler apart won't gain you any more access to it then you already have. It's designed to come out so you won't mess anything up removing and replacing it, but make sure you don't lose the spring and nipple that are inside it. They are vital to keep the brew head from dripping.

  • Starbucks Barista Teardown

    If the screw head is completely stripped out, as a last resort you can pry up one side of the brew screen with a flat blade screwdriver and turn the screen itself with a pair of pliers. This will usually turn the screw as well, and once it's out you can either re-flatten the screen or just replace it with a new one.