Do I need to replace soaking wet insulation resulting from a plugged A/C drain?

Question

I had a company install an A/C evaporator unit on my existing heating system. A plugged drain caused the plastic pan inside the evaporator to overflow with water, which then ran out through the metal housing into the safety catch pan underneath. But the insulation inside the evaporator underneath the catch tray is soaking wet now.

There is no drain hole in the bottom panel, so water trapped with the insulation can only leave via evaporation. I am worried that the insulation will become moldy before it dries out, causing health issues. Currently there is no smell or any other problems.

In order to inspect/replace the insulation, the entire evaporator unit needs to be removed, which would take a considerable amount of time and effort.

Does the insulation need to be replaced or will it evaporate dry before it becomes moldy?

I would appreciate any help.

Answer 1

Insulation can get wet as almost anything can. If you can take the insulation out and dry it properly it will be fine - fan and moderate heat.

Insulation itself does not harbor mold quickly. It is associated with mold because insulation (fiberglass/rock wool) holds water and makes things around it moldy. As long as you get the insulation thoroughly dry within a few days it does not need to be replaced.

Answer 2

I was eventually able to convince the contractor that the unit needed to be replaced. After they removed it, I inspected the insulation in the old unit and it was still saturated, as I suspected, but no mold yet. The water had nowhere to go, and could never evaporate away. They then replaced the evaporator another (twice!) because it was leaking water out the bottom, eventually they realized they were never installing the catch pan correctly. But now the unit is working, almost 2 years later. What a disaster ... never using this company ever again, but I learned a lot about A/C units along the way.