LG Therma V CH16 fault code

What it means

Combined water-sensor fault (CH17 + CH18 + CH19 together)

The water-inlet, water-outlet and e-heater-outlet sensors all read implausible at once. A single sensor rarely fails all three, so suspect the shared harness/connector or the PCB feeding them.

UK models this code applies to

From the LG service literature we hold (LG AWHP Service Manual MFL68682007 (© 2020, R32 Therma V) — error codes + component tables; scope: code SET & fan figure whole-range, compressor winding confirmed 12/14/16 kW, thermistor tables part-level) — not a scraped list.

Now the harder half: proving what caused it

CH16 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.