Horrible musty smell from vents

vln

I had new heat and air installed last July, everything was fine until October. I didn't use either heat or air for a month, and then I turn on the air and it smells TERRIBLE. Like a moldy musty smell comes out of the vents. So I get the HVAC guy out here and he checks the vents, it doesn't smell bad at the return vents or the delivery vents.

He takes off the exhaust pipe from the furnace and it doesn't smell bad. But you can somewhat smell it when you remove the blower motor. Where is the smell coming from?!!? This is a mobile home so you can't clean the ducts. It has been 9 months and the smell is just as bad as it was when it happened sometime in October. Oh and you can ONLY smell it when the fan or air is turned on, for some reason you can't smell it when the heat turns on.

Please help! I am trying to sell the mobile home and I can't have the home inspector smell the musty odor coming out of the vents. Thanks.

joecaption

Is there a vaper barrier under the house on the ground? Is there any standing water under the home?
Go buy a mold detector at Lowes of Home Depot and leave in in the area where the filter in the return air chamber is and see what happens.

Lets face it mobile homes are built cheap, far to often I've seen what looks like black card board used under the home that soaks up moisture, the ducts may have been sealed with duct tape not foil tape that's failed. So all that miosture can get into the ducts.
Just some guesses from what I have found in the past.
(I've owned and lived in two mobil homes in the past so I'm not trying to poke fun at your home)

vln

Thanks, but I can't afford a mold detector at the present time for a home I'm not going to live in permanently. If it was mold, why would it randomly show up then and never go away, not when he installed it? There is no standing water beneath the house, and yes, the "black boards", many are falling, but There is no easy solution to remedy that problem either. I do not think there is any barrier installed underneath.

joecaption

http://www.homedepot.com/h_d1/N-5yc1...&storeId=10051

If you sell a home with a know mold problum plan on spending some time in court.
And any ducts can be cleaned, even in a mobil home. There not removed to be cleaned.

vln

Yeah, no. I am not going to do a mold test. Then I WOULD have to reveal it to a buyer. I am taking 20,000+ loss on this mobile home already. And the ducts, you can see the insulation in them, so they can not be cleaned with a brush.

I have a feeling you think this is a more modern mobile home. it is from 1971 and is located about 2 miles from the pacific ocean. Thanks.

joecaption

Sorry just trying to be real and help.

vln

I'm sorry if I am coming off harsh, but this problem has reached the breaking point, I don't want to turn on the air anymore because of the smell.