I have a Carrier furnace model 58MCA100-16. The past couple days we've been having issues with the furnace turning off rather quickly and not fully heating the house. The LED code on the furnace is 3-1. It blinks 3 times fast and then 1 long blink. After further inspection, there's a significant amount of water leaking from some of the drain tubes inside the unit. Once these are drained (manually by me into a bucket) the furnace operates fine for about 24 hours. Then I need to go back down to the basement and re-drain it manually. I've also noticed the white PVC piping coming from the furnace vent and going up and outside the side of the house has some dripping water on it (not a lot, just a few stagnant tear drops of water are seen on the outside of the pipe). I believe the problem is the 'condensate trap'. The water doesn't seem to be passing through that into the floor drain). I found a replacement 'condensate trap' online for about $15.00, but does anyone know if the issue is more than just that? Why would the PVC pipe going up to the basement ceiling have drops of water on it?

Thanks for your help!