condensate drain issues

[lmei007]

I just bought a 2nd floor apartment and was told by the first floor neighbor that my Carrier FB4ANF030 system was leaking.

The Carrier HVAC is installed next to the bath room. The condensate water is connected to the shower drain on the right side. By looking at the system, I found there are two potential issues there:

1. the vent was sealed, that means there is no vent. should I drill a hole on the cap?
2. the secondary drain is not in use. should I start use the secondary drain and connect it to the same shower drain?

 

[WorthFlorida]

You did not state where the leak is coming from? If it is coming from the air handler you need to flush the drain line with water from a hose or with an air compressor. At the right corner of the ductwork at the floor shows some corrosion so probably is has leaked before and maybe for a long time. It also looks like on the left side there is mold on the drywall.

No hole is needed in the cap and it does not act as a vent. The cap is not glued so it can be removed to clean the drain should it back up. The other drain connection is higher than the connection next it so it won't help any. Heavy mold and mildew will accumulate in the drain pipe and completely block it. A very common problem in the humid south and at least once a year it needs to be flushed out. At least from the pictures, the drain line along the wall does not look like its sloped correctly but that could just be the angle of the picture.

Some air handlers can be mounted horizontally and two or three connection points are usual. The best way is to protect from overflows from the drip pan is to install a Safe-T switch. Where it gets fitted depends on your drain situation. I would redo the connection at the air handler.
https://www.rectorseal.com/safe-t-switch-ss1/ There is also model SS2 with a different configuration. By the pictures it looks like the drain line has been repaired and patch a few times. I would reconfigure the piping using Model SS1. It's all PVC pipe easily available at any hardware store. The Safe T switch can be bought online. It does look like there is a trap below the tee. These can be bought at Home Depot. https://www.homedepot.com/p/Charlot...te-Running-Bend-Trap-PVC027010800HD/204837401

The Safe T switch is a float switch and the two wires get connected to the A wire of the thermostat. When the switch opens the power is lost to the thermostat thus turning off the AC. If the drain line is plugged up you'll need to remove the side cover to clean out the drip pan and check for any mold on the coils. The drip pan is usually very nasty after a few years of use. It's all just routine maintenance.