Sage BES450 / Sage BES870 — Pulsing pump sound during coffee or steam. Rhythmic pulsing is normal pump operation while liquid flows, but the same sound with an empty tank must not continue dry. Preserve the exact display, drink and timing, then perform the official check once. Confirm liquid is flowing and the tank is above minimum; if flow is normal, take no action, but stop immediately and refill if the pump is dry. Keep hands away from hot water, steam, the grinder and moving brew parts. Switch off and unplug before removing a user-removable part; never open the housing, boiler, pump or grinder.
Models covered
Safety first
- Keep hands away from hot water, steam, the grinder and moving brew parts. Switch off and unplug before removing a user-removable part; never open the housing, boiler, pump or grinder.
What the symptom may indicate
Checks in the right order
- Capture the starting point
Photograph or note “Pulsing pump sound during coffee or steam”, the selected drink and what happened immediately before it.
- Make the machine safe
Keep hands away from hot water, steam, the grinder and moving brew parts. Switch off and unplug before removing a user-removable part; never open the housing, boiler, pump or grinder.
- Follow the manufacturer check
Confirm liquid is flowing and the tank is above minimum; if flow is normal, take no action, but stop immediately and refill if the pump is dry.
- Retest once and decide
If the exact symptom clears, observe one normal drink. If it returns, preserve the evidence and contact authorised support instead of repeating resets or guessing a part.
Stop and get qualified help when
- Stop immediately for a hot plug, damaged cable, burning smell, smoke, water near electrical parts, uncontrolled steam, a dry-running pump, a part moving under pressure or the exact fault returning after one documented test.
Next step
Repair, replace a part, or arrange a diagnosis?
Use the checks and stop conditions above to choose a cautious next step. A symptom alone never proves that the appliance has failed.
Resolve it without buying anything
Complete the 4 user-accessible checks in order. If normal operation returns and no warning sign remains, no replacement is indicated.
Replace only the confirmed part
If the checks isolate a worn or blocked component, match its complete reference to the exact appliance model before ordering.
This guide does not identify a replacement part. Do not order a generic component from the symptom alone.
Arrange a diagnosis before replacing the appliance
Stop at any warning sign listed above. A qualified diagnosis should confirm that repair is unsafe, unavailable or uneconomical before an appliance replacement is considered.
Sources used
- Sage — Sage's official manual or model page documents “Pulsing pump sound during coffee or steam” and the bounded user procedure retained here.
- Sage — Sage's official manual or model page documents “Pulsing pump sound during coffee or steam” and the bounded user procedure retained here.
- Sage — Sage's official manual or model page documents “Pulsing pump sound during coffee or steam” and the bounded user procedure retained here.
- Sage — Sage's official manual or model page documents “Pulsing pump sound during coffee or steam” and the bounded user procedure retained here.
Last checked: 30 August 2026