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lifeinthesnaill's avatar
Apr 10, 2016

Both inverters died and now the one's fan runs constantly

I have been operating with a bad deep cycle battery since I bough the motorhome last August. It really wasn't a big deal. I could charge electronics with two 400 watt Cobra inverters while driving. Lights and water pump always worked fine. Rarely plugged in at rv campgrounds. I installed a 100 watt solar panel and solar controller a month ago. Now, even when not driving I could charge electronics as long as the sun was out. The other day I decided it would be nice to be able to actually store power in my battery, so I bought one at Walmart. The Everstart 24dc. Before installing the new battery, I never had any problems charging my laptop, cellphone and camera battery at the same time. The other day, I was only charging my laptop. When I went to unplug it, the inverter started burning up. I could smell it. I opened it up and the two fuses were burned on their negative sides. The other inverter had just randomly stopped working a couple of days before. No signs of it burning. So I bought a new inverter at Walmart 410 watts made by Schumacher. When I charge only my laptop with the new inverter, the fan runs constantly. What is the deal? I have plenty of power. The solar controller indicates the battery is charged and healthy. Any ideas why my inverters went bad and now this one's fan won't stop running? If I just charge my phone, it the fan doesn't run. It's with the laptop charging that the fan turns on immediately. When the old inverter burned, could it have scorched the wires causing them to work less efficiently?
  • Hard to say whats going wrong. Pickup a multimeter at Walmart and check your voltages. At the solar controller, at the battery, at the inverter, even coming out of the inverter if you want.

    I have a 400w no-brand inverter I use to charge my laptop sometimes, and its fan runs too. The laptop has a 110w charger, so that's more than 25 percent of the inverter power, I guess the fan runs when it needs to.

    Charging a phone is only going to need 5-6 watts, so that's a big difference from a laptop.
  • Hard to say exactly. I don't know why you would bother to buy and install a solar panel and a charge controller before replacing a known bad battery.
    The bad battery likely kept the overall system voltage rather low as it was likely a huge current sink. With a good battery your inverter is likely seeing higher voltage than it used too.
    Some charge controllers can be damaged if connected to an array with no battery connection. A bad battery might cause a similar fault. Therefore you may have damaged the charge controller.
    There's not necessarily any problem with the fan running. A laptop could draw nearly 200 watts in my experience. I would expect the fan would run.
  • KD4UPL wrote:
    Hard to say exactly. I don't know why you would bother to buy and install a solar panel and a charge controller before replacing a known bad battery.
    The bad battery likely kept the overall system voltage rather low as it was likely a huge current sink. With a good battery your inverter is likely seeing higher voltage than it used too.
    Some charge controllers can be damaged if connected to an array with no battery connection. A bad battery might cause a similar fault. Therefore you may have damaged the charge controller.
    There's not necessarily any problem with the fan running. A laptop could draw nearly 200 watts in my experience. I would expect the fan would run.


    Thanks for the reply. I won the solar panel in a drawing.
  • lifeinthesnaillane wrote:
    I have been operating with a bad deep cycle battery since I bough the motorhome last August. It really wasn't a big deal. I could charge electronics with two 400 watt Cobra inverters while driving. Lights and water pump always worked fine. Rarely plugged in at rv campgrounds. I installed a 100 watt solar panel and solar controller a month ago. Now, even when not driving I could charge electronics as long as the sun was out. The other day I decided it would be nice to be able to actually store power in my battery, so I bought one at Walmart. The Everstart 24dc. Before installing the new battery, I never had any problems charging my laptop, cellphone and camera battery at the same time. The other day, I was only charging my laptop. When I went to unplug it, the inverter started burning up. I could smell it. I opened it up and the two fuses were burned on their negative sides. The other inverter had just randomly stopped working a couple of days before. No signs of it burning. So I bought a new inverter at Walmart 410 watts made by Schumacher. When I charge only my laptop with the new inverter, the fan runs constantly. What is the deal? I have plenty of power. The solar controller indicates the battery is charged and healthy. Any ideas why my inverters went bad and now this one's fan won't stop running? If I just charge my phone, it the fan doesn't run. It's with the laptop charging that the fan turns on immediately. When the old inverter burned, could it have scorched the wires causing them to work less efficiently?


    I'd say it's normal. I bought one at Wally World as well and the fan runs all the time even with no load. Can't comment on the other issue though so others more versed will chime in I'm sure.
  • IF you never had a problem before and the ONLY thing you did was replace a BAD battery, the odds are you did not connect the new battery correctly. You either reversed the battery cables or you have one of the cables on the wrong post. Doug

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