My dishwasher does not get hot, the waters cold?
A dishwasher, on a normal wash programme will start off by flushing the sump with fresh water, a short fill and a drain, which clears standing water from the appliance, there is always a small quantity of water left in the sump at the end of a dishwasher cycle. This acts as an air break betwen the dishwasher and the drain outlet. Once this initial cycle has completed the dishwasher fills with water to commence the wash cycle..
Once full, the dishwasher commences by washing in cold water for a few minutes, this cold water wash is important. The dishwasher soap dispensor will open to allow the detergent into the wash. At this point the "heat" cycle starts, this can easily be 10 to 15 mins after the dishwasher was started (normal wash 55 or 65 degrees). The time taken for the dispenser to open varies from manufacturer but 10 to 15 minutes will cover most of them.
Electronic dishwasher pcb's will fault at this point with a fault code (F3, F4 are fault codes used by some manufacturers for no heat), unfortunately the fault code of no heat just does not mean the element is faulty. A mechanical timer dishwasher will stick in its programme at this point if the water does not heat. Any of the following dishwasher parts can give the same fault code:
Therefore, no heat in your dishwasher is not an easy fix, the hard part is in determining what component is faulty or indeed if more than one has failed.
It is also possible for the dishwasher electronics to do a self test before starting a cycle, any component failure detected can stop the programme from starting.