I have an odd problem with our dishwasher. On the 70deg intensive program, the water does not heat, and items come out dirty, wet and cold. On the 50deg economy and 60deg quick programs there is some heat, but nowhere near what there has been in the past. I was going to replace the heater, but I’m not sure now, as there is some heat on some programs. Any advice as to what this might be please?