Victron MultiPlus-II 24/3000 making a weird clicking noise when idle — anyone else had this?

Just noticed my MultiPlus-II 24/3000 has started doing a faint but noticeable clicking every few seconds when it's in inverter mode with low load (we're talking just the router and a couple of USB chargers running, so maybe 30–40W). It's not the relay click you get on startup — it's more of a repetitive tick-tick-tick pattern. Been running it for about 14 months on the narrowboat without any issues until now.

Running 24V with a 200Ah Fogstar Drift LiFePO4 bank. SOC is typically sitting between 60–90% when this happens, so it's not a low-battery thing. I've had a poke around in VictronConnect and nothing looks obviously wrong — no alarms, and all the voltage/current readings seem normal.

Has anyone actually experienced this on a MultiPlus or similar Victron inverter-charger? I'm wondering if it could be something to do with the Power Assist settings or maybe the search mode kicking in weirdly, though I thought search mode was only a thing on the older units?

Worth raising a support ticket with my installer, or is this a known quirk I should just live with?

Reply by CamperTel:

@LindaClark90 — that clicking at low load is almost certainly the PowerControl or dynamic power assist relay cycling. The MultiPlus-II has internal relays that can chatter a bit when it's hunting between modes under very light loads.

Worth checking a couple of things:

1. Search mode / Sleep mode — if enabled, the inverter periodically "wakes up" to check for load. That click is the relay firing. You can adjust the sensitivity in VictronConnect.

2. AC input threshold — sometimes it's toggling between inverter and passthrough if your grid/shore connection is borderline.

Connect via VictronConnect or VEConfigure and have a look at your search mode settings. Tweaking the minimum load threshold often sorts it completely.

If the clicking is rapid or irregular rather than rhythmic, that's a different story — worth logging it via the GX device if you have one.

@LindaClark90 — worth checking whether the click coincides with the fan spinning up or down. On my 24/3000 the internal fan has a very specific low-RPM "tick" at thermal transition points, even when ambient temps are modest. It's a known characteristic rather than a fault.

Also check your minimum output power setting in VictronConnect — if it's set very low, the inverter can oscillate between sleep/active states depending on your load profile. Bumping it up slightly (or disabling PowerAssist if you're not using shore power) sometimes eliminates it entirely.

If the click is genuinely rhythmic and mechanical-sounding rather than electronic, I'd log a ticket with your Victron dealer regardless — the 24/3000 has a 5-year warranty and that's absolutely worth exercising if something's physically amiss.

Reply by FormerTeacher50:

@LindaClark90 — I had exactly this on mine about a year ago. What nobody's mentioned yet is the relay switching between search mode and active inverting. When load drops very low, the MultiPlus hunts around trying to detect whether a real load is present, and that clicking is often the transfer relay toggling.

Worth popping into VictronConnect and checking whether Search Mode is actually enabled — if it is, try disabling it and see if the clicking stops. It's under the inverter settings. Solved mine completely. Search Mode is great for battery conservation but can cause that characteristic rhythmic clicking at minimal loads.

If disabling that makes no difference, then @CamperTel and @LochLinda's suggestions are definitely worth pursuing too. Nothing to worry about structurally, but it's worth getting to the bottom of it.

Reply by ShaunTaylor94:

@LindaClark90 — one thing worth adding that nobody's touched on yet: have a look in VictronConnect at your ESS or inverter mode settings, specifically the "minimum SOC" and any scheduled charge windows if you're running ESS. I found on mine that the system was repeatedly trying to switch between modes as the battery hovered near a threshold, which caused a rhythmic clicking from the relay. Tweaking the minimum SOC by just a few percent stopped it completely. Also worth checking your DC cable connections are properly torqued — loose connections can cause similar relay chatter under fluctuating micro-loads. Dead easy to overlook but surprisingly common cause.

Reply by JohnChapman:

@LindaClark90 — just to add something a bit different to what's already been said: that rhythmic clicking at very low loads can sometimes be the MultiPlus cycling in and out of its dynamic cutoff / search mode. If your battery voltage is sitting at a borderline level, it'll repeatedly attempt to supply load, sense it's marginal, and back off — rinse and repeat. Worth checking your battery state and connections first. Also, have a look at the "Search mode" setting in VEConfigure — some folks find disabling it (if you don't need the power saving) stops the behaviour entirely. Might be worth a quick check before assuming anything hardware-related. What's your battery setup — lithium or lead-acid? That can make a difference to how the inverter behaves at idle.

Reply by FrankMurray:

@LindaClark90 — worth checking your battery connections while you're at it. I had a similar clicking on my 48V system and it turned out to be a slightly loose negative terminal on the battery bank causing tiny voltage fluctuations that were confusing the inverter. The MultiPlus is pretty sensitive to supply voltage wobbles at low loads. Give all the terminals a proper torque-check with a calibrated wrench — Victron specify the correct torque values in the installation manual. Sounds daft but it sorted mine completely. Let us know what you find!

Reply by Thommo53:

@LindaClark90 — worth checking your battery voltage too. If your 24V bank is sitting a bit low, the MultiPlus can go into a sort of reduced power state and you'll sometimes get that clicking as it's essentially hunting around trying to maintain the output. I've seen it on mine when one of my AGMs was starting to sulphate and pulling the bank voltage down unevenly. Popped a battery monitor on it and the culprit was obvious straight away. If you've got a BMS or a BMV-712 fitted, have a look at what the individual cell or battery voltages are doing when the clicking occurs — might tell you something useful. Could be completely unrelated but it's a quick check before diving into anything more complicated.