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ewarnerusa's avatar
ewarnerusa
Nomad
Mar 13, 2015

How to quiet down a noisy inverter fan?

Hello,
I have a cheap ebay PSW 300 watt inverter. But it works great for my needs. It has a cooling fan that only comes on when demand warrants it. But the fan has become really noisy, sounds like a bad bearing type of noisy. I see that the fan is still spinning when it is making this noise, but it sounds awful. Typically the sound tends to go away as the inverter warms up, but lately it seems like this takes longer and longer. I'm thinking a drop of lube on the fan axle should do the trick, but I thought I'd at least solicit some input before I opened it up to try this. Thanks.
Ed

29 Replies

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  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Mar 13, 2015
    For fun I'd try and fix it - what have you got to lose?

    These little guys are measured in millimeters not inches.

    If your fan has three wires it must bereplaced by a fan with three wires.

    Cheap fans use porous bronze bushings not ball bearings. Look on the rear of your squealing fan. Note the label. It will have a power rating in milliamps and volts. Your new fan sgould have the same voltage and have almost the same milliamp number.

    jameco.com

    Or

    allectronics.com

    Are a good place to find a big variety of fans. Be sure your new fan is ball-bearing.
  • ewarnerusa's avatar
    ewarnerusa
    Nomad
    Mar 13, 2015
    LOL, My inverter collection is already up to 4...
    I was just thinking about that yesterday when I thought of the Morningstar inverter as a replacement. I gambled in the beginning and got this small PSW inverter for cheap that met my needs. But then I kept gambling when looking for a bigger PSW inverter which is why I have 4 now but only use 2. If I had just bought a nice large one in the beginning, I'd probably have saved money in the long run. Isn't that how it usually works? Funny because with my mountain bike components I learned this lesson years ago.
  • JiminDenver's avatar
    JiminDenver
    Explorer II
    Mar 13, 2015
    My little Power bright cw150 is wonderful except even left out in the truck, I can hear it's fan running at times. I can either get a slightly larger inverter that wont need the fan under small loads or go with the Morningstar fanless 300w inverter.

    In the case of your fan getting larger, small inverters are pretty inexpensive.
  • azrving's avatar
    azrving
    Explorer
    Mar 13, 2015
    I had the same problem with a cheap model. I never hear any noise from my xantrex. I think you need to try and crack it open and replace the fan or do like some of us and start an inverter collection.
  • Second_Chance's avatar
    Second_Chance
    Explorer II
    Mar 13, 2015
    If the fan is anything like the fans in computer equipment, there may be a rubber plug on the back of the motor housing. I have re-lubed these in two ways: 1) remove the plug and drop in the smallest amount of 3-in-1 oil possible (often with a toothpick), or 2) if the plug isn't removable, use a syringe and needle (I'm a retired Army nurse) to inject a minute amount of 3-in-1 or sewing machine oil. It's easy to over-lube these motors. The alternative is to find a replacement fan (of better quality) by matching the size, voltage, and CFM specs.
  • ewarnerusa's avatar
    ewarnerusa
    Nomad
    Mar 13, 2015
    Yeah, I haven't fully thought the idea through or opened up the inverter. Just a brainstorm of what seems like a simple solution. If I have to invest anything to "fix" this cheap unit, I'll probably just look into replacing it instead. I hear the Morningstar ones are nice and don't use a fan at all.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Mar 13, 2015
    Put it somewhere you cannot hear and run an extension cord.

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