AC sweating

[Tinkerer2]

The air handler is in an unconditioned closet in the garage. The closet is generally cooler than the garage and still is. However, we are getting condensation on the air handler cabinet. Unit is an up flow Carrier. When I noticed the condesation, there was enough to wet the top of the box it is sitting on. I've attached photos of the unit, closer photo where the air handler connects to the ductwork, 2 photos of right side showing condensate droplets, and a photo of the back where more drops can be seen. Condensation also occurs on the left side but it was too close to the wall for a photo. Humidity here has been around 80 for days. Filter is clean. Even though the drain line was dripping outside, I flushed it yesterday anyway with a gallon of hot water. I dried the cabinet with a towel yesterday too.

This morning the condensation is back. When I flushed the drain line yesterday, I closed the blue handled valve to prevent the water from backing up into the air handler pan. Today, I left the valve open and poured it very fast to fill the funnel hoping it would back up into the air handler pan and either clear that line or possibly break up whatever may be in the pan. Condensation is back on the outside of the air handler cabinet. This is something new as droplets were not seen in the past. Granted, the tape between the air handler and the ductwork may have been damp before, droplets were never seen.

Unit is 2 years old. We have not adjusted or closed any registers in the house. Thermostat is set on 72.

Ignore the rust trail on the bottom front of the unit. That was an issue that I had soon after moving in and the AC tech resolved it.

Any ideas?

 

[Jim greengo]

I'd say it's normal,weather/temp related.
Give it a few days and see what it does as things cool down.

 

[Bert_]

Not insulated well enough, none of them are. The metal is below the dew point. You could add insulation to the outside of the duct if it's happening often.

A good reason not to put HVAC equipment in unconditioned space.

 

[American Locomotive]

It's extremely humid and the air conditioner is cold. It's going to have condensation on it. What's the dew point in your area right now? Any weather website or app should say it.

 

[Tinkerer2]

According to WeatherBug, Temp is 88, Feels Like 100, Dew Point is 77 and Humidity is 70

Just haven't noticed this much condensation in the 2 years we've been here.

 

[American Locomotive]

A dew point of 77 means anything that is 77 degrees or colder, will form condensation. Seems pretty reasonable for the casing of an air conditioner to be that temperature.

 

[fitter30]

First the inside insulation will get wet lose it R factor. Then the cabinet starts to sweat. That one reason units in uncondition space should have safety pan under them. Insulating the cabinet would help but it has to air tight just like the duct work seams that are sealed.

 

[Tinkerer2]

So, I'll just keep watching it and see how it goes. I just didn't want there to be a major problem and ignore it.

 

[beltfeed]

If you keep the garage closed most of the time, try running a dehumidifier in the garage. That will pull a lot of moisture out of the garage air.