Yes, that is pretty nasty looking and something should probably be done.

The question is what. First off where do you live, what is the age, type and condition of the rest of the equipment, what is the RH in the home and type and condition of the home?

Off the top of my head I would say turn it off for now but a lot more needs to be known to make a educated guess.

 

Thanks for the quick response. I appreciate any input.

The home was built in 1992 and is 3200 sq ft. I had this downstairs unit replaced with a York D1NZ036N07206A about 3 years ago. That is when I realized the humidifier was down there. I finally got to tinkering with it last year and noticed the condition of the duct, so I think the majority of the damage was done before I repaired and re-hooked up the humidifier to the new York. The mold, however does look happy now.

The humidifier is a Skuttle Auto Moist Model 592.

I'm not sure of the relative humidity of the home, but it is dry in here now that the furnace is on.

 

Oh, I live in Huntersville, NC... just north of Charlotte.

 

The location [climate] and indoor RH really need to be known in order to determine if you even need one. Get a cheap one at HD or someplace and check it.

 

Ok, i was able to get an inexpensive gauge. I live in the Charlotte, NC area and the RH in the home currently is 40%. Is that an indication that i would or would not need a humidifier? What are the guidelines?

 

It's a good sign you may not need it, 40% is decent without a humidifier at the current temps.

I would clean up the mess and continue to monitor it.

 

You shouldn't even need a humidifier until overnight temps are consitently below about 35F outdoors. Even lower if it's newer construction and fairly tight in terms of air leaks.

Also, stema or misting humidifiers need a minimum amoutn of airflwo ot evaporate the water injected into the air stream so that moisture doesn't condense inside the ductwork... as you see. You might also set it up to ONLY run when the furnace or heat pump is running.

40% is about where I'd start using a humidifier down to about 30F outdoors. Below that I would keep dropping it to avoid moisture on windows and worse inside walls.

 

Thanks, guys. I really appreciate the help. I think I'll get this mess cleaned up and then stick to the in-room type of humidification as needed with colds et all. ...looking forward to a healthier family in the future!

 

The white stuff in your photo could be mineral deposits left by moisture evaporating off the insulation. The black stuff is either insulation showing through the white stuff, or that unnmentionable entity that people really get freaked out over.

If you want to retain the humidifier so you have whole-house humidity control, consider having the existing insulation removed and the ducts cleaned, then externally lined with insulation, if that's possible. That way, any water that collects on the interior surface does not become an unmentionable entity food factory.