AC drip pan (internal) poor design?

[Larry Barowski]

While fixing a clog in the internal drip pan drain of my home's AC, I noticed that the drain is not on the very bottom of the pan. Even when the pan is fully drained there is about 1/8 inch of water in it, and this water is (just barely) in contact with the bottom of the cooling fins. Is there any reason to have water in the pan at all times, or is this an idiotic design, as I suspect? The pan is PVC, so I'm thinking of adding a drain to the bottom of the pan by drilling a hole and gluing a flanged pvc end to the bottom, if there is no good reason not to.

[Don Young]

"Larry Barowski" wrote in message news:YtudnWmO_Ooph6nYnZ2dnUVZ [e-mail]...

I like for drain pans to drain completely but many don't. It is usually not a problem as the slight amount of water that does not drain will evaporate fairly rapidly if no water is draining into the pan. I would not modify the pan drain.

Don Young

[Larry Fishel]

I'm no expert, and I don't know if this is universal, but at least some AC units (like the one I bought) are specifically designed so that the water that condenses on the inside coils is held in the pan below the outside fan, which picks it up and flings it onto the outside coils where the evaporating water increases the cooling efficiency. The drain is only to make sure the water level doesn't get too high...

[sylvan butler]

Until I read your response, I was exclusively thinking of central air or split A.C. units. Your response didn't make any sense to me until I remembered window A.C.'s. Different perspectives. :)

Obviously in the case of a split unit, the condensation pan is designed to be a long way away from the outside (hot) coils so such a design optimization is unlikely.

Though it can work well when the evap and condenser are close enough!

sdb

[Larry Barowski]

I was thinking maybe some water in the pan prevents crud from building up, or something like that. If there is no real use for it, then I plan to make the modification.

[Larry Barowski]

I can feel a big change in AC temp when rain hits the coils, even when there is no outside temperature drop (here in SW Florida, it often rains with no temperature drop). I wonder what the difference in efficiency would be? Since my drip drain comes out near the outside unit, I'm tempted to try to rig something up.

[Mark Lloyd]

Water conducts heat much better than air.

[Don Young]

"Larry Barowski" wrote in message news:i-GdnVZZmorHhqvYnZ2dnUVZ [e-mail]...

Won't have any significant benefit and likely to cause problems. This has been discussed many, many times. Do a Google search for the discussions.

Don Young

[sylvan butler]

Funny, those discussions have left me with the opposite impression. Of course, there is the caveat that the unit may not work properly with significantly improved cooling...

sdb

[Zephyr]

Condensate removal is important and to prevent mold or algae build up is also important. But so are mechanical limitations. If it's a small package window air conditioning unit we're talking about, then all the postings are correct. The condensate is removed from the living area's and drained back to the condenser to aid in efficiency [evaporative condenser cooling.]

Perhaps you could check and see how level the unit is? Generally most are installed with a 1/4 bubble lean [from level] to the back so the condensate drains easily. That way, when the unit is idle, the evaporator is not exposed to excessive water storage.