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elhajj33's avatar
elhajj33
Explorer
Oct 11, 2015

Help! First problem with RV: loud buzzing in bedroom

So...picked up our 09 Fleetwood excursion 40x and am presently at a campground. There's a loud buzzing in the master bedroom. It's not the breaker box (if I put my ear at the breaker and go up and then to the right, the buzzing gets louder)

I checked the battery compartments and it seems not to be emanating from there. It's definitely higher up. It's so loud I can hear it on the outside of the coach.

If I put my ear to the coach, I can hear a buzz/whine (sounds like a transformer)

I checked the inverter (magnum m2000) and it's not that. Any thoughts???
Class A

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  • elhajj33's avatar
    elhajj33
    Explorer
    Oct 11, 2015
    I turned off all the breakers including the mains and the noise persists. What's the ATS. It doesn't sound like a fan. More of a transformer like sound.
  • wolfe10's avatar
    wolfe10
    Explorer
    Oct 11, 2015
    ATS is the likely suspect.

    Turn off the main 120 VAC breaker in your coach 120 VAC breaker box. If it continues to buzz, you know it is in your ATS, as no power is going to anything else in the coach. This assumes you have eliminated your inverter/charger as the noise source. If not, turn it off so it does not invert when you turn off the main breaker.
  • Blaster_Man's avatar
    Blaster_Man
    Explorer
    Oct 11, 2015
    Stand where you can hear the buzzing and have somebody turn off the circuit breakers one at a time...until the buzzing stops. Then you'll know what it is.
  • elhajj33's avatar
    elhajj33
    Explorer
    Oct 11, 2015
    Toddupton wrote:
    Refrigerator fans?


    Fridge is in the front though and the buzzing is all the way in the back above the engine.

    It's so odd!
  • bluwtr49's avatar
    bluwtr49
    Explorer II
    Oct 11, 2015
    That noise would be characteristic of a transfer switch. They sometimes develop a hum that can be very noticeable.

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