It’ll all come out in the wash
Our Aquarius 6kg washing machine works fine when on shore power, but on our Victron Multiplus 12/3000/120-16 inverter (fed by 5 x 110Ah leisure batteries, with or without engine running) the drum just oscillates. The manual gives power consumption of 0.644 - 1.048kWh at 230 volts. Is there a solution? PHIL AND SUE BOSWELL, via email
TONY REPLIES: Modern machines are fussy about AC, but as you have a pure sine wave inverter it stands the best chance. As it works on shore power, that indicates the problem is on the boat.
If the LEDs on the Victron are showing a fault condition, the problem could be related to low battery voltage, faulty batteries, or undersized inverter 12v supply cables. Check the adjustable inverter output voltage. The consumption you quote in kWh gives little indication of the maximum current demand. Is the inverter (rated 2500W) and its cabling able to supply the load demanded? It is possible the motor starting surge, plus the heater current draw, is too high for the inverter, so try running it with the temperature set to cold.
If you can measure the 12v input voltage at the inverter when the washing machine is turned on, or get Whirlpool to give you the maximum current (amps) or power (kW) the machine draws, that may also give a clue.
Alternatively, it could be caused by the inverter not being capable of supplying the motor starting surge current with a sufficiently accurate frequency.
I fear you need to consult a well qualified and experienced marine electrician who should be able to take the measurements required and assess the cable sizes.
A washing machine with a mechanical (not electronic) timer, conventional induction or brushed motors and the heating element disconnected might have a better chance, but I doubt such a machine is now available in the UK.
Is the inverter big enough to run a washing machine?