How To Seal Air Handler Plenum In Attic

Make sure that all metal fittings are firmly screwed together on four sides then covered with liquid or tape mastic and fully re insulated.

How to seal air handler plenum in attic. The air in your vented attic is hot and humid just like all outdoor air in florida. When working with mastic wear disposable gloves and spread it carefully since its glueyness makes cleanup difficult. Create or modify an air sealed closet to contain the air handler and the return air plenum. Learn how to seal yo.

Energy saver first look into the attic when helping improve a home s ene. Air sealing your ducts is cheap and easy and it save s a lot of money. I had them seal all of the inlets to the air handler the supply and return plenums all the attic holes. There are two main ways to solve this problem.

When the hot humid attic air contacts the cold duct or the cold duct boot the moisture in the air condenses on the cold surface just like the condensation that happens on a cold can of beer. Aluminum tape and mastic can be found at well stocked hardware stores or through amazon. Use aluminum tape to seal joins between two flat smooth surfaces usually metal and mastic for irregular surfaces such as wood. As shown in the infrared image on the right the plenum is not air sealed so hot attic air is being pulled into the air handler closet.

There are many different ways to seal this crawlspace including plastic sheeting the application of foam insulation to the foundation walls on the inside of the crawlspace and more. I even had them open the air handler and seal inside following manufacturer s guideline. Then finish up by sealing the access hatch with self sticking foam weatherstrip photos 10 and 11. I missed out on giving specific instructions on one part and they messed it up.

If your hatch rests directly on the moldings like ours did add 2 1 2 in wide stops around the. Here are the most common reasons for air handlers sweating so you can stop the condensation. I asked them to seal the refrigerant line and all they did was to put. The grille in the photo on the left brings air into a return air plenum under an air handler platform.

However air handler sweating is different. For repairing simple leaks in the air ducts. Moreover the excess moisture can lead to a damaged plenum mold or termites. Otherwise in the summer months the warm air that is under your home will rise up through the floors and cause your air handler to sweat.