Steam knob on Oscar turns freely, does not turn the steam on or off anymore.

you need to replace the steam valve

when you descale your machine, how did you drain the water? I think the scale particles clogged your steam pipe. And also if you had put a lot of descaling chemicals, this chemicals can eat up the heating element. If you can remove the heater and check it physically and also cleaning and removing the scale inside the tank will help.

yes, something has burned out.

turn unit on ...switch on ... turn water steam control to open position ,,,,,it should sound load then go quite as air lock will come through .. hope this works if not i repair you need spares .. ..postal service too 07779933829

run some vinger and water through it a few times then try it out again.

I had the same problem, two green flashing lights with one red (water) all 3 would just keep flashing and not turn solid. No coffee can be made or hot water. I could not pump prime. The problem was the steam wand was blocked with old milk residue. It needs unblocking or you will never pump prime. I could not unscrew the steam wand...so I let it sink in a glass full of hot water for a few minutes and then turned the water knob counter clockwise to push out the softened residue. After that, everything was good. When water started flowing out of the steam wand, the red light turned off and the green lights turned solid. The obvious answer to why you can't pump prime is there is a blockage somewhere and best to start with the steam wand. --Mabada

If steam wand is not blocked then the problem is on the inside of the machine, try descaling the machine that might clear the blockage in the steam line.

When you open the knob is the wand hot? If yes then the holes at the end of the nozzle is plugged, use a paperclip or needle to clear.

Hi
I think you steam knob is out of adjustment. This valve the the knob turns opens a needle, so when you close the knob it is just allowing the needle to seat. If you turn the knob harder you move the valve away from the needle, so when you try to steam everything has expanded and the valve does not touch the needle, and it won't open.
To fix.
The top comes off by removing the screw on the top back where the water tank locks in. Once the screw is removed the put both hands on the side of the machine near the top and with your 2 index fingers, push the top forward. This will push the top of the face plate forward and release the top.
Once the top is off hang it over the back for know.
You will need a #2 Allen wrench. Rotate the knob all the way counter clockwise. You will notice that there is a cam that rotates with the knob. On the back side of the cam you will find a hole. Inside that hole is a #2 Allen screw. Loosen the screw and then without moving the cam rotate the know all the way counter clockwise, then tighten the Allen screw. This is how you adjust the Solis SL machines steam valve.
To reassemble.
The top of the face plate locks into the bottom of the front part of the top, so when you put it back together slip bottom of the face plate into the machine, then put the top on the face plate so the front of both is flush whit each other. Then push down and back on the top and it will lock in. then put the screw back in and your done.

I used brute force. Remember to turn it clockwise to close.