AC/Heat Duct Dust?

[Mike Brown]

Anyone getting large dark grey dust like particles blowing out of their AC/Heat duct in the main salon? If our unit doesn't run for a day or two it'll blow out clumps of dark dust all over the seat by the vent. I've tried running a vacuum cleaner hose down the duct but can't get far enough to do any good. No apparent rips or tears the duct hose. Can't figure out why it's happening. Anyone else seeing thus?
Mike

[Bruce Bogdanoff]

I am running my heater regularly now that I am heading south off the Bahamas in my B-40. I do not notice the particles that you are mentioning. I would suggest two things to try to see if it fixes the problem. First, clean the two intake screens under the berth by the mast support. There are two screws on each frame and can come of easily or pull them out from inside the berth. Mine are filled with lint after one  month of constant use. The second is to vacuum the entire area by the compressor.

Let us know if this improves the condition.

[Mike Brown]

Bruce thanks for the response. Yes I've already done both and do so on a regular basis. I'm beginning to think that the duct tubing or something inside the fan box is flaking apart. I've looked down the tube from the top but don't see anything. My next move will be to open up the duct from both ends. I thought I'd see if anyone else has seen the issue before doing so.
Mike

[James Taylor]

Mike

The heat/ac distribution ducting on our b43 has a black plastic exterior then, going internally, there is red or yellow insulation that covers a thin wire wound thin black plastic interior air tube. Maybe moisture developed at a low point and slowly ate through the interior plastic? Maybe its something in the distribution box or off the fan motor wrapping? Who knows, I'd just take the salon ducting/ distribution box out, shake it out, and try to figure out what the heck is going on. Might have been a critter in there (hope not)! I think that particular ducting is pretty easy to remove and replace.

Good Luck

James

[Mike Brown]

James yes you may be right. Looks like I'm going to have to tear it apart to find the cause.
Mike

[Mike Brown]

Finally found the cause of the particles coming out the AC/Heat vents. Turned out to be a heavy accumulation of dust in the fan box. Vac'd it out, cleaned the filters and problem gone. Looks like the filter at the compressor isn't up to the task. More frequent cleaning of the filters and fan box are in order.

Mike