My A/C Duct Has Fallen Off Under My Mobile Home – Now What Do I Do?

Its mid-June and you have been waiting until the last possible moment to turn on your mobile home central air conditioner. You hear it running but nothing is coming out of your vents and you are not only sweaty, but frustrated as well. Don’t sweat it. You can perform this common mobile home repair yourself.

First things first, lets determine what type of central A/C you have. If you look outside and see a much larger size unit compared to your neighbors, you most likely have whats called a “self-contained unit” or a “packaged unit”. You can further confirm this by looking at the rear of the unit and you will see two round ducts that enter into the underside of your home. These two ducts are approximately 12″ in diameter and usually are of the flexible type with a plastic sheathing. This unit has its own blower package built together with the evaporator coil and condensing coil. The problem you are experiencing are more common with this type of central A/C.

You have two areas that need investigation.

First locate the cold air return. This is a large vent that most likely is centrally located along the outside wall on the floor. This is where the air conditioner draws interior air and conditions it. Remove the grill and ensure that the filter material does not need to be replaced or cleaned. Most of the time the filter material is reusable and simply needs to be cleaned. Further check to see that the duct work is fastened completely to the sheet metal box that the filter is slipped into.

The second area will require a little more effort. Open the skirting to your home’s underside and locate where the other round 12″ duct attaches to the main duct of the home. Clean pieces of cardboard work very well to lay down on the ground prior to entry. Cardboard will keep you clean and help with sliding in and out from under the home. Most of the time when this problem occurs, the solution is under the home. The 12″ supply duct is prone to falling off the collar of the main duct. A tell-tale sign of this is when you open the skirting, you get a blast of cold air hitting in the face. Your A/C has been cooling the underside of the home. Repair people who typically don’t have mobile home repair experience are the ones usually to blame for the poor connection.

To repair the connection, slip the duct back on the collar. use sheet metal screws with small washers to ensure a long-lasting connection. Do not use duct tape to seal the connection. This is an inferior product that will not last. Instead, use a brush-on duct mastic sealant and coat the connection making sure you seal all the way around. This is a bit messy but will guarantee you will never have to go under your home and repair it again.