<p>I’m not an A/C technician, but I stayed at a Holiday Inn Express last night.</p>
<p>First of all, it doesn’t do any good to put Freon (puron, or other such) without first sealing the leak. It is just going to leak out. If you want to get by for the summer, then fine. But you are looking to keep it for 5+ more years.</p>
<p>Thinking about how an A/C works: you have the outside compressor where it compresses the freon gas, gas gets hot, hot gas is run through the outside coils, that cools it off, gas is allowed to expand where it turns into a cold liquid.</p>
<p>The cold liquid is piped into the home. The cold liquid is then piped through the Heat Exchanger, where it warms up the liquid back into a gas. The gas is then piped back out to the compressor outside.</p>
<p>The heat exchanger is where the inside air is cooled, and water condenses in the process. That condensate drips to the drip pan. The drip pan channels the water to the drain pipe.</p>
<p>So, other than on the Heat Exchanger, where can water condense? It can condense on the sides of the air ducts. It can also consense on the cold pipe feeding the heat exchanger. The drip pan should extend to the air duct walls and collect condensate from the walls. The cold pipe should be wrapped in foam to keep water from condensing on it.</p>
<p>So, what can low freon do? The pressure in the system will be low. When the compressor outside compresses the gas, the low pressure keeps the gas from heating up as hot. Thus you have warmer cold liquid comming back into the house. I can’t see how being low on freon would cause condensate problems. The system tends not to work, or work as well. Not cause water to condense where it shouldn’t.</p>
<p>So, back to the heat exchanger. That’s the place where water is condensing. Properly installed, the water will drip onto the drip pan. Typically, the heat exchanger is A shaped, with the peak in the middle. The area under the middle is open (to allow the air to flow through). By gravity, the water drips along the sides of the A to the outside edges of the heat exchanger. So, the drip pan only covers the outside edges of the Heat Exchanger.</p>
<p>Possible problems with the drip pan:</p>
<p>1) Drain line clogged (you checked that).
2) Crack in the drip pan.
3) Drip pan does not cover the entire bottom edge of the heat exchanger.
4) Drip pan is not level, so the water is pouring over an edge.
5) Bad seal between the edge of the drip pan and the side walls allowing water to drip down the walls between the gap.</p>
<p>Other possible problems:</p>
<p>Heat exchanger is not properly positioned over the drip pan.
Heat exchanger is not level, so water is dripping off the middle, rather than the ends.</p>
<p>Given that it has worked for years, and only now is giving you a problem, things I would check are:</p>
<p>1) Is the humidifer leaking?
2) Drip pan drain
3) Crack in the drip pan.
4) Seal between side wall and drip pan
5) If you remove the humidifier, sometimes you can look at the Heat Exchanger. If so, see if you can see where the water is coming from.
6) Is the Heat Exchanger still level?</p>
<p>It is possible that when the technician looked at your heat exchanger, he repositioned it before pumping in more freon. If he didn’t secure the heat exchanger, it just might have come loose again. Thought: In the process of comming loose, the movement of the heat exchanger might have caused a crack in the pipe that let the freon leak out.</p>
<p>If I were you, I would open up the system and try to see where the water is coming from.</p>