Ok this will be quick and of value to someone facing this issue with their BES 900 Series Coffee Machine. And I mention it as its not the usual cause*1.

Ok what’s the issue, the machine hangs at about 75 degrees on the display. And fails to reach the usual 93 degrees. With the lid up, you will notice the Steam Boiler is cold. Now as this happened after a descale I suspected the worst(thermal fuse or element, both a major pain to resolve, the fuse is the most common after a descale but so hard to get out and replace).

However a quick inspection of the error codes told another story. Error code 20, which is ‘Steam Pump or high water probe level error” and an error 30, “Steam boiler leakage”, which means the steam pump is running but no water is being detected arriving in the steam boiler.
So steam pump not filling steam boiler, thus steam boiler not activating. Strange thing is I did not hear the steam pump running at all during the boot up. Perhaps it is dead.

I pulled the red high level probe connector off and the pump started, I grounded the connector and it stopped. Which indicates all is normal with voltage supply to the pump. However the pump sounded subdued and quiet, like it was pushing against a blockage. Perhaps that’s why I did not hear it during the boot up phase. So with the machine now off and unplugged I removed the high level probe (covered in scale) and disconnected the pump inlet hose from the pump bypass. I then tried to blow through the tube, I huffed and I puffed but could not blow air through the inlet tube. It was well and truly blocked.

And as you can see from the photo, a big block of scale was blocking the tube. I removed this and the issue was resolved. This was a hell of a lot easier than replacing a fuse or complete boiler. However the clip that holds the inlet tube in place is a real bastard to get back in. If there is an easy way to do it, I don’t know it what it is.
Grab a Service Kit and replace the hot orings while you are at it.
I hope this helps.

Scale blockage in the boiler inlet tube

Just in case I didn’t make it clear, the usual cause other machine not reaching the operating temperature of 93°C is because an Element has failed. There may be a thermal fuse Open circuit, an element Open circuit or voltage it’s not being switched to the elements.

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