The attic AHU condensate overflow pan drains right out the side of the attic and comes out over the driveway. I’m thinking the point of this is that, if the main condensate drain plugs up, the homeowner will see water dripping out of this drain, which will should alert them that something is up and it’s time to call the HVAC company.
Is this a common thing? It actually seems like a good idea.
I see it quite frequently, especially in older homes that have had central heat & air added. The HVAC guy I deal with said the auxiliary drain should terminate in a conspicuous place if the AHU is above a living area and no overflow cut-off switch is installed.
Yep, that’s what it is, retrofitted central AC, the home has hydronic heat with baseboards. Kind of better than the overflow cut-off alone, since your AC continues working and you can clear the main drain at leisure, so to speak.