Manganese fouling early detection

A variable-speed-driven borehole pump at Syleham, with a documented history of manganese fouling. Because the drive adjusts to hold duty, a pump losing hydraulic performance does not simply slow down. The compensation shows up in the electrical data before output falls far enough to be noticed on site.

On 28 April, SAM4 raised a process change alert: a downward trend in load, with the VFD compensating for the pump's reduced performance. The guidance named the likely cause, fouling from manganese build-up consistent with this asset's own failure history, and pointed inspection at filters, valves and the pump house.

Manganese build-up inside the pump, matching previous findings on this asset. The fouling degraded hydraulic performance gradually rather than causing a hard stop, and the variable-speed drive masked it by working the pump harder to hold duty. The pump was never blocked, which is precisely why the problem stayed invisible to conventional monitoring until output had already dropped.

SAM4 detected the load trend and the drive's compensation, and raised a process change alert on 28 April with named inspection points. Northumbrian Water confirmed reduced output the same day and scheduled a swap. The pump was pulled on 30 April and replaced with a spare; the removed unit was inspected, manganese fouling confirmed, and sent for repair.

A degrading pump was identified, confirmed and replaced within four days of the alert, as a planned intervention with a spare on hand rather than an emergency response to a failed asset. The new unit returned immediately to its expected power and frequency range, and SAM4 indicators were back at healthy levels by 2 May. The removed pump was recovered intact and sent for repair rather than written off, saving £12,500 against the cost of replacement, with the further benefit of a planned outage in place of a reactive emergency job. Detection came from the pump's electrical signature alone, with no additional instrumentation on the asset.