Humming noise when plugged into shore power

[Big Papa]

I'm a new toy owner. Picked up an '87 Minnie Winnie a month ago and it appears to be in good shape. However it makes a humming noise, more than it should I think, while plugged into shore power. Any thoughts? 

[jjrbus]

If the humming noise is coming from the electrical panel I would waste no time on it, simply replace it with something new. Progressive Dynamics makes replacement units that are far superior to what you have now.     http://www.progressivedyn.com/rv_products.html

Only my opinion of course.    

[Maineah]

The older charger/converters had big old ugly transformers in them. As transformers age they kind of loosen up and tend to hum more. The modern ones no longer have them and are light years ahead of the old ones. It's a real good up grade for your MH.

[Big Papa]

Ok guys, thanks. I'll do it. Keep you posted. 

[DanAatTheCape]

the older convertors have old style transformers that do hum.  Most have a cooling fan that will kick in after it warms up.  humming is normal.

that said, if your house battery is discharged and/or not capable of holding a charge, the transformer in the power converter will be working hard, just as it will if you run dc lights or appliances.

many are quick to change the old style power converters - they are not neccessarily a bad thing.  I would check your house battery though.  Most auto parts/ walmart will load test it.   Deep cycle batteries can have short lives if repeatedly run down to nothing and left discharged - both common in the rv world.