2004 G3500 Express - Clogged condensate drain and Low refrig
Posted: Sat Jun 06, 2026 1:19 pm
Had to add refrigerant this spring. I had a bunch of used R134a from earlier RV projects in a can, so I just put that in. Seems ok for about 2 weeks since. Hopefully it holds.
On the drive up to VT this week I noticed condensation leaking out in front of the passenger tire - way further forward of the normal drip location. Opened the hood and the HVAC box was leaking from seam - condensate had backed up and was oozing out of where it shouldn't. There's a big exit area at the bottom of the box with a rubber flapper over it. I snaked my hand in there and pull out a couple handful of pine needles and leaves, but didn't get the gush of water I expected. It seemed later like it was dripping from the right location, so hopefully at least the box isn't full of water still.
I should pull it apart and clean it... I hope the evaporator core didn't corrode out from touching crap.
On the drive up to VT this week I noticed condensation leaking out in front of the passenger tire - way further forward of the normal drip location. Opened the hood and the HVAC box was leaking from seam - condensate had backed up and was oozing out of where it shouldn't. There's a big exit area at the bottom of the box with a rubber flapper over it. I snaked my hand in there and pull out a couple handful of pine needles and leaves, but didn't get the gush of water I expected. It seemed later like it was dripping from the right location, so hopefully at least the box isn't full of water still.
I should pull it apart and clean it... I hope the evaporator core didn't corrode out from touching crap.