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2002 dodge caravan leaking water from a.c

i have a 2002 dodge caravan that leaks water on the passenger side floor board when th a.c is on. i have had it to three mechanics and each have said they fixed it by cleaning the tube thats on the left side of the fire wall. one even put a sealer around the tube and fire wall saying it was leaking threw the factory sealent. but like old faithful the van leaks still what can i do?

I guess that you don’t have a cabin filter, as by now, you probably have a compost heap growing in the evaporator chamber.

The evaporator chamber is under your dash on the passenger side. When the AC is operating, the refrigerant turns from a liquid to a gas inside the evaporator. This makes the evaporator, which resembles a small radiator, very cold. Warm moist air is blown through the evaporator, the air cools and the moisture condenses on the evaporator. The moisture, now water drips down the evaporator to the bottom of the chamber.

The bottom of the chamber resembles a shallow bathtub or shower pan. It has a drain at the lowest point that has a tube connected to it, The tube goes through the firewall and open to air. The water drains onto the ground, except when the tube gets clogged up.

When you have outside air selected, air is drawn in through an opening under the cowling. The cowling is the piece of plastic or metal at the base of your windshield, just behind the hood. Air goes down to the fan where it is blown into the system. Overtime, dust, bits of leaves and needles gets sucked into the fan and blown onto the evaporator. Some of it washes down into the drain and clogs it. The standard fix is to blow compressed air up into this tube, but if there is enough accumulation of debris in the evaporator chamber, it just clogs back up.

Sometimes you can clean this chamber out by removing the fan and reaching through the duct to the evaporator. You might be lucky and the bottom of the chamber might be removable without pulling the whole evaporator out (Are you listening HONDA?). Worst case, you have to have a HVAC technician drain the refrigerant and remove the evaporator to clean it.

Best case is that the bottom is removable, second best is that you drain the water out, remove the blower motor, then between compressed air blowing the compost away from the drain and using a small vacuum or your hnd to remove the muck.

BTW, if the AC doesn’t seem to be working quite as good as it used to, this is why. It will work better after cleaning.

thanks keith will give it a shot will let ya know