What happened in the guest room?

This picture came up on Facebook recently. I immediately knew why my friend’s guest bedroom ceiling looked like this. Do you?

It is all because of this little part. It clogged.

Because AC units make air that is cooler than surrounding air, there is condensation. This goes into a tube and is pumped out. When this works, all is well. But mechanical pumps fail. Tubes get clogged. Bad things happen.

This won’t matter much if the HVAC unit is in the basement; if it leaks, it will leak onto a basement floor. But, when the HVAC unit is in the attic, it leaks through the guest room ceiling. Insurance companies and homeowners, alike, are unhappy.

Many houses around here retrofitted central AC by adding an HVAC unit in the attic. It seems to me that about half of the ones I see have no pans and look like this:

 

 

 

What they should look like, it this. If the pump leaks, the fluid will collect in the pan (green arrow.) The pan drains out through the white PVC tube (red arrow.)

The guest room ceiling is saved!