The AC plant: what happened, step by step
What this page tells you: the plant’s history in one table, who is involved, and the possible causes raised so far.
Facts as recorded by the owner. Root cause not determined. No cause is asserted on this page.
M/Y Kaloda is a 32 m Azimut Grande delivered in June 2023. Her chilled-water plant (Climma/Veco CWS MODUL 3603, Gulf spec, three modules of 120,000 BTU) has stopped producing any cooling. This page puts the plant events in date order, with photos.
Who supplied and services what
| Role | Organisation |
|---|---|
| Yacht builder; installed the plant | Azimut (Azimut Benetti S.p.A.) and its Asia after-sales service |
| AC plant manufacturer | Veco S.p.A. (Climma brand) |
| Manufacturer’s regional dealer | SEA Power Systems (Singapore) |
| Local service contractor | ASAP Marine (Thailand) |
| Independent inspection | An independent HVAC inspector (Thailand), 29–30 Jun 2026 |
| Hull insurer | Pantaenius |
| On-board isolation transformer maker | Bi-mec |
Plant events in date order
| Date | What happened |
|---|---|
| 31 Mar 2023 | Plant commissioned at the yard. Yacht delivered 26 Jun 2023. |
| Feb 2024 | ReplacedThe manufacturer’s service network found debris (metal, plastic, rust, mud) in the chilled-water loop and little or no glycol; inverter heat exchangers were fouled and modules were overheating and blowing fuses. The loop was cleaned and refilled; heat exchangers, actuator valves and solenoids were replaced. The builder covered this work. |
| Mar–Jul 2024 | Repeated flow-sensor failures (units 2, then 1), stuck fan-coil valves, CAN and seawater-pump issues. |
| Apr–Jun 2025 | Manufacturer’s fan-coil capacitor recall carried out on board by ASAP Marine. |
| Aug 2025 | FailedUnit 3 inverter circuit board failed. The manufacturer advised the warranty had expired, based on the commissioning date. |
| Dec 2025–May 2026 | ReplacedUnit 3 oil discharge; DIS-VOLT (low-voltage) events recorded, seen alongside generator stalls; unit 3 inverter replaced again (photos of the burnt drive taken 29 Jan 2026). |
| 29 May 2026 | FailedInsulation tests on all three compressors: C1 about 109–110 Ω to earth (failed); C2 about 23.5–23.8 MΩ (healthy); C3 about 3.2–3.4 MΩ (low). Windings balanced. |
| 29–30 Jun 2026 | Independent inspection: unit 3 line reactor W-phase terminal charred. The reactors are open-frame units mounted beside seawater piping. |
| 29 Jul 2026 | FailedUnit 2 flow fell from 6.71 to 0.00 m³/h and the inverter plate reached 62.3 °C before a flow alarm (code 7). All three modules out of service. |
| 30 Jul 2026 | Joint video call with the builder and the manufacturer. |
| 3 Aug 2026 | RestoredUnit 2 restored temporarily (flow-sensor bypass, two fuses replaced); a new flow meter later read 7.04 m³/h. |
| 19 Aug 2026 | FailedAfter a shore-power loss, compressor 2 failed: about 5.6 Ω to earth on all phases. No cooling since. |
| 7 Sep 2026 | Replacement plant ordered through the manufacturer’s regional dealer to start the lead time (12–16 weeks as stated by the dealer). The removed parts are kept. |
| Sep 2026 | Thermal survey of the on-board isolation transformer (photos). |
Possible causes raised so far (none confirmed)
These are hypotheses people have raised. None has been tested or confirmed. An independent investigation is needed to rule each one in or out.
| Hypothesis | Facts recorded so far |
|---|---|
| Debris or low glycol in the chilled-water loop led to overheating of the drives | Debris and low glycol found Feb 2024; sediment still found in the strainer Jun 2026; inverter overheating codes logged from Jan 2024 (see the fault-code table). |
| Stray current or electrolysis | Raised by the dealer, who noted it would need separate confirmation. The isolation transformer is always in circuit on shore power; hull potential reads protected; underwater anodes largely intact; other seawater equipment on the same sea chests unaffected. |
| Supply quality (shore power, generators, transformer) | DIS-VOLT events seen with generator stalls; compressor 2 failed after a shore-power loss; phase-sequence lamp reads “WRONG”; neutral current 10.95 A with harmonics. |
| Moisture or heat in the machinery space | Reactors open-frame beside seawater piping; machinery space reported about 38.6 °C with seawater about 31.7 °C. |
| Design or installation of the plant | Manufacturer electrical diagram for the installed model received 12 Oct 2026; installation manual for the installed model still requested (the manual on board is for CWS MODUL 2402). |
Insulation pattern: all three compressors show balanced windings but low insulation to earth. What that pattern points to is one of the questions we would like an expert to answer.
Photos
All photos: photo gallery. Measurements and fault codes: technical facts.