Hi all.
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I have a few year old AC180 installed in my van. My van has a Victron inverter to supply AC power for charging the AC180 while engine is running via AC input port. It also has 100W solar panel to charge AC180 via DC input port. I also have a DC line from the van’s 12VDC port to the AC180 DC input port (only active while engine running). The solar panel and the 12VDC van port are connected in parallel to the AC180’s DC input port. I have the AC180 in Silent Charging Mode, which only draws up to 260 W when charging, so that it doesn’t exceed the 375 W output capacity of the Victron inverter. This has all worked great for a couple years now.
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I drove my van for several days ending on October 31, 2025. The state of charge was 100% at end of that trip. Since then it has been parked beside my house, with minimal solar charging since then (I’m in Washington State and we don’t get much sun during winter). I checked the AC180 3 months later on February 3, 2026 and found that the AC180 was off. Upon pressing the ON button, it turned on, showing 0%, 0 watts in, and with red “Low Voltage Alert” indicator, and then turned itself off. The display was on for only 4-5 seconds.
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Coincidentally, the van’s starter battery was also completely dead, but this appears to have been caused by the passenger door latch having failed and the door not being closed all the way and so the “door ajar” light was on, thus likely draining the starter battery over 3 months. I don’t think that this has anything to do with the issue with the AC180.
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I check the solar panel DC output and the Victron inverter AC output and all was working well.
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I brought the unit into my house for several days to allow it to adjust to room temperature. I then plugged it into standard US AC wall outlet. I verified that the cable was passing 120VAC to its Bluettie connector. Upon plugging it into the wall, the AC180 display turn on and again displayed 0%, 0 watts in, and the red “Low Voltage Alert” indicator and again turned itself off after 4-5 seconds.
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Regardless, I have left it plugged into the wall for 24 hours. When I try to turn it on, same thing happens: 4-5 seconds of displaying 0%, 0 watts in, and red “Low Voltage Alert” indication.
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I tried pressing DC and AC buttons together simultaneously for 10 seconds. Nothing happened.
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I tried pressing ON button for 30 seconds. This only resulted in 4-5 seconds of displaying 0%, 0 watts in, and red “Low Voltage Alert” indication.
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I plugged a 24VDC source into the AC180 DC input and, as usual, got 4-5 seconds of displaying 0%, 0 watts in, and red “Low Voltage Alert” indication, although there was a sound like an internal relay turning off at the end of the 4-5 second.
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During all of above, there were no AC or DC loads on the unit.
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The unit has been working very well up until now. No major charging or discharging issues and it has served well in my van running a small refrigerator, a small fan and other small loads.
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Seems that the battery level in the AC180 is too low to run its own charging circuit (which I consider to be poor design on the part of Bluetti who should have thought through such a scenario).
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Any suggestions?
If the battery is “deeply” discharged, the BMS may not negogiate charging even if you plug it into the wall. It’s known as overdischarging. On a freshly calibrated battery when the display hits 0% the system has 10% left because 10% is reserved for BMS. Problem is when you get to 0% you have no idea how much of that 10% is left. If the display turns on, there’s at least SOME % left, but there’s a point when BMS just shuts off to protect battery and will ignore charging. When it becomes overdischarged, there’s no really no option but to bypass the BMS, and to do so involves opening the case or sending back to Bluetti.