hotpoint washer dryer e15 error and cycle not working beyond 'heating'?

I have Hoptpoint washer dryer wd72. I got e15 error code, checked and cleaned the black outlet pipe and waste pipe, but still getting error code. I put the machine on a acrylics programme to see if its working and now it does not go beyond the 'heating' function. After about 20 minutes i cancelled the cycle, opened the door there was a burning smell in the drum. Can anyone please advise as the what the problem is. Thank you.