One of the steam wands won't stop. I have turned off the machine and it stops, but when I turn it back on, the wand starts up again. What should I do?

The steam valve is not closing. In such a case water finds an east exit from the machine where there is no back pressure.

Repair the steam valve.

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Hi. Make sure all your buttons are off. (switches all facing the same direction). Then make sure the tap is turned off. Switch main power on. Then switch the coffee on. you should hear the pump start. usually loud at 1st, then it will get quiter as the water is pumped up through the group head. When water is pouring through the group head, switch off the coffee button. Now let it finish heating. If you can get to this stage, then everything is ok. If you cant get it to this stage then you have a problem with the machine. Most likely a themostat on the boiler. Darryn REPAIRER

Hi
With the proper descaling media ( not vinegar) mixed in your water tank. Turn the machine on and run water through the wand immediately, then turn off the wand and let it run through the brew head for a couple (8) of seconds then open the wand again for a couple (8)seconds, then turn off the machine and let it set for 15 minutes. Repeat this procedure until the tank is empty. Then rinse everything out and repeat this procedure with out turning the machine off. Just open and close the knob every 8-10 seconds until the tank is empty again. Have something under the brew head and wand to catch the water. Yo can stop the process to empty the containers is they get too full.

Sounds like the steam wand is getting blocked some where either at the metal end or in the parnello wand if you machine has one at the end of the steam wand, if both of those are clean then try this push in on the steam knob if that works then tap rod assemble or steam valve needs to be replaced, make sure to ask about the stainless steel valve instead of the plastic one.

Have you tried cleaning out the machine? My steam wand started just spraying out a steady stream of water but was not heating up. I used the cleaning solution CLR (8 parts water, 1 part CLR) and let it run through the steam wand for awhile. At first it just kept streaming out then all of a sudden it stopped. I still kept it on just to see what would happen. After about 10 seconds all of a sudden the steam wand shot out whatever had clogged it and it works perfectly again! I had only used the machine about 10 times before this happened. I had not been cleaning it well after each use back then. Now I definitely do.

The boiler is contaminated with milk and needs to be descaled and cleaned.

How long have you had the machine? Use a straight pin and poke the opening of the wand. It may be blocked. If the bottom of the wand can be removed, use some pliers, and CAREFULLY remove it, soak it in hot water. Rinse it thoroughly, and replace it back on the machine. If you cannot remove the wand, turn the machine upside down, and check the opening to the wand. It most likely is stopped up. Run vinegar and water through your machine once a week. Calcium build up does the same thing. Good luck! Happy Lattes!

Try this from another post. It should help.

The steam wand began to seriously leak but a call to Starbucks Customer Service line and I was talked through how to adjust it so that the leaking stopped. It requires taking off the top/back panel of the machine (6 philips screws) then using a small allen key (1.5 mm I believe) to loosen and adjust a plastic oblong donut-shaped thing (a "cam" actually) on the shaft of the steam knob... no more drips.
The key to prevent dripping is to open the steam knob without putting pressure on it when it gets to the full-open stop position. Cranking it too hard when it comes to a stop in the full-open position will slowly move the cam out of position. Then the shaft doesn't fully seat inside the machine anymore and won't fully shut off the water to the steam wand. Then, no matter how hard you crank the knob in the shut-off position it will still drip. The purpose of the cam is to stop the knob from complete unscrewing and it also turns the pump on and off for the steam wand. The cam adjustment is very small but completely solves the dripping problem. Seeing inside the machine made me realize how easy it would be to repair problems as long as I can get the parts from Starbucks or perhaps Saeco.

The coffee brews fine but the steam wand is not working.
Pressure build ok.

The steam wand has to be removed to be cleaned properly. Unfortunately, this procedure is not outlined in the manual. Just cleaning the wand on the outside or using a clip to clean the tip is not enough.

The other end of steam wand where it connects to the pressuring cabin actually swivels around a fitting. It is this fitting that you need to thoroughly clean. Years of using the machine can cause calcification around this fitting.

If you look under this end of hte steam wand, you should see a philllip-headed screw. Before you loosen this screw, you have to remove the grey trim so that the entire wand can be remove.

Once the entire wand is removed, what I just described will be much clearer.