So I have a uk spec multiplus ii 12/3000 that’s less that 6 months old making a pretty horrible noise. I’m guessing it’s a case of making a warranty claim but my dealer is totally ignoring emails and the support function on the Victron web site just emails the dealer on my behalf. So does anyone have any ideas with what the issue might be - it’s hard to describe the noise (except to say it sounds like a tractor ticking over) so I made a video and uploaded it to YouTube. It’s only about 5 mins long so if you have time I’d appreciate your thoughts.
So I managed to eventually get hold of the dealer and they confirmed the noise is not normal so a new motherboard and a new fan is being sent to me to self instal. Sending it back for repair was also an option but I’m quite happy to swap a fan and board over. Hopefully that’ll fix the issue.
Finally got the parts from Victron/supplier today and installed them (main board and fan) - takes a bit of jiggling to get the board out and back in. The fan is very easy.
The difference is night and day! Don’t get me wrong, there is still what I would describe as normal fan noise, but the horrible, loud, tractor diesel engine noise that appears under load has gone, and so has the tinny rattle (which we suspect was one of the relay coils). I’ve been advised that the noise was ‘PWM knock’ and isn’t uncommon where the frequency of the PWM signal isn’t high enough and there is no smoothing circuitry.
I understand that Victron actually issued a fix for this (a small PWM smoothing board between the fan and its original 2 pin connection) and then modified the main boards on newer builds. Mine was manufactured in June 2024 and I purchased it in December 2024, and the replacement board was manufactured October 2024, so the evidence would suggest that there are some unmodified main boards still being used because the difference in noise is unbelievable and can’t really be mistaken.