Check the heat exchanger (condenser)
The heat exchanger — the condenser block that pulls water out of the warm air — needs checking and cleaning, or on Bosch self-cleaning models, is being rinsed automatically.
What it is for
On AEG and similar models, open the plinth flap, take out the condenser and rinse its fins as the manual shows. On Bosch self-cleaning models, the symbol means an automatic rinse is running: do not pull out the container or cancel the programme.
Makes differ, check your machine’s manual: the same drawing can mean different things on different brands, and only your model’s manual says exactly what a programme does, how hot and how long.
- What it looks like
- A block of fins drawn as a grid in perspective (Bosch), or stacked lines with an arrow through them (AEG).
- Names makers use
- Automatic heat exchanger rinse (Bosch); Check the heat exchanger (AEG); Condenser
Where makes differ
Bosch’s grid means “Heat exchanger is cleaned automatically”; AEG’s lines-with-arrow means check it yourself. Whirlpool’s heat-pump dryer shows a separate bottom-filter symbol for the filter in front of it.
Often confused with
The fluff (lint) filter — or on some models the filter in the base — needs cleaning before the dryer can work properly.
Other symbols with the same shapes
Sources
No single published standard defines washing-machine or dryer programme icons, so this meaning is taken from 2 makers’ own guides and manuals, each fetched and read on the date shown:
- Bosch: Bosch Home UK — Tumble dryer symbols and settings — Dryer display: Automatic heat exchanger rinse symbol (a grid in perspective) — “Heat exchanger is cleaned automatically. Do not pull out container or cancel programme”. Checked 2026-09-25.
- AEG: AEG — LAVATHERM 7DEE835R / 7DEE832R tumble dryer user manual (PDF) — Display: “indicator: do the check of the heat exchanger” (stacked lines with an arrow); condenser lid and cover shown in the product description. Checked 2026-09-25.
Written in our own words; quotations are the makers’ wording.