The electric heater is turned off. Activated by tripped overheat protection on the electric additional heat, high flow temperature or too high temperature in electric additional heat. The automatic trip fuse to the electric additional heat may have been tripped due to, for example, a short circuit.
UK models this code applies to
From the Worcester Bosch service literature we hold (Worcester Greenstore LECP Installation, Commissioning and Servicing Instructions 6 720 806 768 (2013/02), §21.8 categories + §21.10 alarm functions + §21.13 information log (render-verified)) — not a scraped list.
E21.E2 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.