Prima LPR 600- boiling dry?

Hi, I have a Prima LPR 600- 8545 600 15810 dishwasher.
Recently, when I put dishes in the dish washer, they don’t come out clean. The machine has not given an error code, but I noticed, that after the cycle, there is no water in the reservoir under the screen in the bottom of the dishwasher, where there is usually a few inches of water even after the cycle has finished. Water does feed into the machine at the beginning of the cycle, but during the middle of the cycle, the machine begins to make a noise that I can only compare with a kettle boiling dry. If the machine is opened at this point, it is clear that the heating element in the machine is actually boiling the machine dry, and the rest of the cycle runs for the normal amount of time, but there is no water in the machine/ circulating around the machine. Have you heard of a problem such as this before? Is it the heating element itself that needs replacing, or is there a sensor that would normally cause the heating element to switch off, which is malfunctioning? I would appreciate any insight you can offer into this problem and suggestion of parts you think may need replacing. Thank you