The pump may be operating normally but unable to draw water into the hydraulic circuit. Common causes include an incorrectly seated water tank, trapped air, an unprimed or restricted water filter, limescale build-up or another blockage in the water path. Start by checking the water tank and filter, then try priming the system using the hot-water function before investigating a possible pump fault.

Yes. Air trapped inside the hydraulic circuit can prevent the pump from drawing water correctly and may cause it to sound noticeably louder than normal. This commonly happens after the water tank has run empty, following a water filter change or after maintenance. Refill and correctly seat the water tank, then try running the hot-water function to help prime the system and restore normal water flow.

Yes. A blocked, incorrectly fitted or poorly primed water filter can restrict the supply of water to the pump. New filters can contain trapped air if they haven't been prepared correctly, while older filters can become increasingly restrictive with use. As a troubleshooting step, temporarily removing the filter can help determine whether it is responsible for the reduced or missing water flow.

A new water filter can contain trapped air and may need to be correctly primed before use. If air remains inside the filter, the pump can struggle to draw water through it, resulting in reduced or no water flow and sometimes a louder pump noise. Remove the filter, prime it according to your machine's instructions, refit it securely and then run hot water to help restore normal flow.

Yes. Heavy limescale can restrict the internal water circuit enough to reduce or eventually stop water flow completely. If the water flow has gradually become weaker before stopping, scale or another restriction within the hydraulic system is particularly worth investigating. Completing the correct descaling programme is a sensible first step before assuming the pump itself has failed.

Not necessarily. A pump often becomes louder when it isn't receiving enough water, which can happen if the water tank is empty or incorrectly fitted, air is trapped in the system, the water filter is restricting flow or there is a blockage within the water circuit. If the basic water supply, filter and priming checks don't restore normal flow, the pump, valve or another internal hydraulic component may require further diagnosis.