MultiPlus 12/3000/120: Been running without problems in the 18months I've had the boat. Have noticed fan coming on at times in the past, but can't recall the specific conditions of charger/inverter at those times.
Today for first time, when in "on" position and genset running, noticed the battery voltage slowly dropping, eventually down to 13.8v. This was whilst still in absorption stage. We were running no more than around 200w of AC equipment at the time.
Switched the unit off and then back on a few minutes later. Went straight to flashing "temperature" LED. Switched off again.
Switched on again about 45min later, with genset still running, and unit turned on as usual and went to charge mode, absorption, with about 40amps going to batteries. Voltage around 14.5v, as usual.
Ran 1500w vacuum for about 30min, along with another +- 200w of other equipment, so maybe 1700w total. Charge mode continued as usual, still with around 35 - 40 amps going to batteries. Nothing out of the ordinary here, but during this time, I never heard the fan come on and battery voltage remained constant, as per usual.
Unit is mounted in open, beneath nav table, so no issues with ventilation. Ambient temp around 27 Celcius.
My question is, given the above scenario/conditions, should I have heard the fan come on, or should I suspect a failed fan? Case is warm to the touch, but I've never felt it before with overheating in mind, so have no comparison.
Been running normally for the past 90min, in charge mode, without issue.