Replacing a Sanisplit MK Grey Water System on a 75ft Yacht

At Rem Yachts Services, we regularly work on grey water and black water discharge systems aboard yachts. This job, carried out on a VanDutch 75, perfectly illustrates the importance of an accurate diagnosis before replacing any equipment.

The captain contacted us after a failure of the grey water discharge system. The shower and washing machine were no longer usable, as the waste water could no longer be properly discharged. Left unresolved, this type of fault can eventually cause water to leak into the bilge, leading to further damage and unpleasant odours.

Diagnosing the Fault

As always, the first step was to carry out a full electrical check.

The measurements confirmed that 24 volts were reaching the Tecma macerator pump correctly, which immediately ruled out a power supply fault or a faulty fuse.

Dismantling the system then revealed a pump in very poor condition. Significant signs of wear were visible, with fluid leaking from several points where there should have been none. Everything pointed to the pump having run under excessive strain before finally failing completely.

The diagnosis led to the conclusion that replacing the system was the most reliable solution.

Installing the New Sanisplit MK System

Once the parts arrived, a new Sanisplit MK system was installed.

During testing, a new issue appeared: this time, the 24 volts were no longer reaching the system. A new round of troubleshooting was immediately carried out.

The checks identified a faulty fuse in the yacht's electrical panel. Once it was replaced, power was restored and the installation could be completed.

Function Testing

Once the system was connected, testing was carried out using the manual push button located on the side of the Sanisplit unit.

The system immediately returned to normal operation. The shower and washing machine drains were successfully tested, confirming that the entire installation was working properly.

The captain and crew were thus able to rely on a fully operational discharge system once again.

The Importance of a Thorough Diagnosis

This job shows that one fault can sometimes hide another. On the first visit, the pump was properly receiving 24 volts, and its condition confirmed that it was no longer working. When the new system was brought back into service, a fuse then blew, creating a second, unrelated fault.

Without a methodical fault-finding approach, it would have been easy to wrongly conclude that the new equipment was defective.

At Rem Yachts Services, every job is carried out following a rigorous method to identify the true source of a fault and ensure a reliable, lasting repair.

Need a Sanisplit Repair or a Tecma Pump Fixed?

We work on all types of yachts, providing diagnosis and repair of Sanisplit systems, replacement of 24V Tecma pumps, 12V and 24V electrical fault-finding, and maintenance of onboard water systems.

Based on the French Riviera, we cover Cannes, Antibes, Golfe-Juan, Monaco, Saint-Tropez, as well as the main Mediterranean ports on request.