We have had a Miele g646sc dishwasher for 16 years which has worked faultlessly. Recently after a bang (near the programe controller) it continued to run through the cycle. When restarting later more bangs from same area and an investigation. The pcb had a blown triac which I replaced. It ran again without problem until the start of drying when there was a bang again and the same triac blew. The heating element works fine as does circulation pump and discharge pump. The drying fan is free to spin. I would appreciate any suggestions what could be causing the short.Thanks