kevinj wrote:1) Does the fact that we have cold water suggest that the heater element is broken?
Possibly. Resistance check required. Burnt out wiring possible, fault with pcb or underfilling - there is a diaphragm switch in the heater box.
kevinj wrote:2) Why does this then create an infinite wash cycle? Is the cycle timed or is there some kind of control mechanism that's waiting for the water to be hot before it can continue?
PCB is "holding" waiting for correct temperature to be achieved
kevinj wrote:3) If the element is broken then what part number would I need and how much is the part?
491756 - about £80. firstname.lastname@example.org
will get you one promptly.
kevinj wrote:4) How do I get at and replace the faulty part?
We can't walk you through it. You can access the heater terminals by removing the r/h side panel, physically changing it involves removing the entire stainless cavity.
Stay safe, power off for anything other than observation.