Today I descaled my NS Oscar after the the descale, I turned on the machine and notice power light is on, heat light on, and when I push the brew button the pump also work, pumping water through the brew head, but the water is not hot so obviously no steam is produce, seems like the machine is not heating up, anyone ever had this issue? How can I troubleshoot this?

Is it possible that I might have blown the heating element, during the descale I emptied the boiler & refill the boiler twice.

Take the cover off and on the right side of the boiler is the safety thermofuse that you can reset by pushing the button.

Mine was popping that thermofuse and when that would happen, the heater would not work anymore.

From what happened with mine, it turns out that it is a symptom of potential problems that need to be addressed.

Mine were a clogged valve at the group head, lose wiring connections by the thermofuse/pressurestat, and a pressurestat that was set too high.

I rushed my NS Oscar to the ER, luckily there is a repair shop near my house, the culprit is the blown fuse, today I went to bring the oscar home, repair cost $20, lesson learned, if you own an Oscar do not try to descale your machine by yourself, there are too many things that can go wrong in the process.