The brew unit is where ground coffee is compressed and hot water passes through to make your drink. Coffee grounds, fine particles and natural coffee oils gradually collect around the brewing chamber, filters and moving parts. Regular cleaning removes this build-up and helps maintain consistent water flow, brewing pressure and movement of the brew unit.

A dirty brew unit can eventually cause slow coffee delivery, weak or inconsistent coffee, unusual noises and difficulty completing a brewing cycle. Heavy deposits can also restrict filters and prevent moving components from operating freely. Cleaning the brew unit regularly can help prevent a simple maintenance issue developing into a machine fault.

This depends on the machine and how frequently it's used. If your machine has a removable brew unit, a regular rinse—often weekly—is a sensible routine, but always follow the cleaning schedule specified for your machine. Machines with non-removable brewing systems may use an automatic cleaning programme and cleaning tablets instead.

Usually, no. Many removable brew units are designed to be rinsed with clean lukewarm water rather than detergent. Washing-up liquid can remove lubrication from moving components or leave residue behind. Check the instructions for your particular machine before using any cleaning product directly on the brew unit.

A small amount of loose ground coffee around the brew unit area can be normal. Grinding and transferring coffee into the brewing chamber inevitably creates some fine particles. If you're finding excessive amounts, however, check that the brew unit is correctly fitted and that the coffee funnel and surrounding area aren't becoming blocked.

Can a dirty brew unit cause my coffee machine to stop working?

Yes, in some cases. Heavy coffee deposits can restrict water flow or interfere with the movement and positioning of the brewing mechanism. The machine may then struggle to brew, make unusual noises, stop partway through a cycle or display a warning.