Water in return: A/C overflow backup...help

Altho I usually do a good job of taking care of home maintenance, I really screwed up on this one. Four days before I snowbird back from FL to NJ, I decided to check my A/C overflow line. Opened the t-valve I installed between the A/C itself and the line exit, and water started to come out...of course, indicating that there was a blockage between the A/C (but not at the drip pan exit) where the water exits. Got a friend's vacupump and got rid of the gunk. However, things aren't all that simple, as when I checked the big, main, return duct, which lies behind the A/C, the insulated walls were wet, but not flooded. I don't know for how long this condition has been going on, and as I'm returning to NJ in four days I have great concerh on what to do to dry things up...or even figure out what kind of damage there may be.
I've put 3 jars of DryRid in the return, sprayed heavily with Lysol, and have my home maintanence warrenty folks coming Monday afternoon to look at the A/C and make sure all is properly drained. So I guess my questions are: What can I do within the remaining four days to hasten drying and prevent mildew? I know I should get the insulation out, but I may not be able to. And, what should make sure that the maintanence folks do?
Thanks, Adam
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Adam writes:

Run the A/C flat out to lower ambient humidity as much as possible. Apply gentle heat (clamp-on flood lamps work well) and air circulation (fans) to the wet area. Gentle heat plus circulation will dry things in a matter of hours.
If your A/C ducting is fiberglass board, it will not be harmed. Gypsum board can usually take a few soakings.
Lysol was a mistake. More water. Mildew is not inhibited by medicinal odors, although it smells like you did something.
Dessicants (DryRid) are not effective except in tightly sealed spaces that are not opened, and quickly spend themselves. Time constant then is still days or weeks.
Beware of clean-up crews that will descend wanting $100s or $1000s to do what you can do rather easily yourself. They will shake their heads, and give you grim looks, and poke around with fancy looking meters with needles pointing to "pay these guys NOW whatever they ASK", all designed to justify absurd prices. Take their free diagnosis but do the cure yourself.
If the dwelling is vacant, snowbird, make sure you have humidity control while you're away and a backup way to read it. Sling psychrometers are cheap and accurate, train your neighbor to sample your air.
And WHY did you have a valve on the condensate drain??? You DO have a 2nd (backup) condensate drain pan and line, right? You must assume the main one will clog, and have an alert system that tells you it is clogged.
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Richard J Kinch wrote:

Warranty folks came and didn't hose me (suprise, suprise). They made sure that I had gotten all the gunk out of the drain line and that everything else was in order. However, they did nothing to reduce the wet insulation in the return box. So, I'm leaving the fan in there and have my humidistate controling the A/C, no heating light, though. Not dry yet, but getting there. Got a house sitter while I'm away and he'll check things out for me.
Finally, just want to clear the "valve" issue. Not really a valve. I put a T into the drain line with a plug on the top of it. This way by easily removing the plug, I can pour in chorine to flush the line every month...as I should have been doing all along.
Adam
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</PRE> <BLOCKQUOTE type="cite"><PRE wrap="">What can I do within the remaining four days to hasten drying and prevent mildew? </PRE></BLOCKQUOTE><PRE wrap=""><!----> Run the A/C flat out to lower ambient humidity as much as possible. Apply gentle heat (clamp-on flood lamps work well) and air circulation (fans) to the wet area. Gentle heat plus circulation will dry things in a matter of hours.
If your A/C ducting is fiberglass board, it will not be harmed. Gypsum board can usually take a few soakings.
Lysol was a mistake. More water. Mildew is not inhibited by medicinal odors, although it smells like you did something.
Dessicants (DryRid) are not effective except in tightly sealed spaces that are not opened, and quickly spend themselves. Time constant then is still days or weeks.
Beware of clean-up crews that will descend wanting $100s or $1000s to do what you can do rather easily yourself. They will shake their heads, and give you grim looks, and poke around with fancy looking meters with needles pointing to "pay these guys NOW whatever they ASK", all designed to justify absurd prices. Take their free diagnosis but do the cure yourself.
If the dwelling is vacant, snowbird, make sure you have humidity control while you're away and a backup way to read it. Sling psychrometers are cheap and accurate, train your neighbor to sample your air.
And WHY did you have a valve on the condensate drain??? You DO have a 2nd (backup) condensate drain pan and line, right? You must assume the main one will clog, and have an alert system that tells you it is clogged. </PRE></BLOCKQUOTE> <DIV>Thanks for the help.&nbsp; <BR>Warranty folks came and didn't hose me (suprise, suprise).&nbsp; They made sure that I had gotten all the gunk out of the drain line and that everything else was in order.&nbsp; However, they did nothing to reduce the wet insulation in the return box.&nbsp; So, I'm leaving the fan in there and have my humidistate controling the A/C, no heating light, though. Not dry yet, but getting there.&nbsp; Got a house sitter while I'm away and he'll check things out for me.<BR><BR>Finally, just want to clear the "valve" issue.&nbsp; Not really a valve.&nbsp; I put a T into the drain line with a plug on the top of it.&nbsp; This way by easily removing the plug, I can pour in chorine to flush the line every month...as I should have been doing all along.<BR><BR>Adam</DIV> <DIV>&nbsp;</DIV> <DIV><EM><FONT face=Arial size=2>Actually, chorine bleach is NOT the preferred method now. Any tech with any training will actually use what is called a Gallo Gun on each spring service.</FONT></EM></DIV> <DIV><EM><FONT face=Arial size=2>Chorine can do more damage than good to the AC coil itself, IF you do not have a P trap inline.</FONT></EM></DIV><EM><FONT face=Arial size=2></FONT></EM></BLOCKQUOTE> <BLOCKQUOTE dir=ltr style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV><EM><FONT face=Arial size=2>As far as the wet insulation....you have two choices, in a case like this....replace the insulation or box, or allow it to dry out. We insulation is NOT EVER covered under warranty, as a clogged condensate drain is NOT a warranty issue...it is a maintence issue..</FONT></EM></DIV> <DIV>&nbsp;</DIV> <DIV><BR><BR><BR><BR></DIV><PRE class=moz-signature cols="72">-- To email, erase "forgetit"</PRE></BLOCKQUOTE></BODY></HTML>
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*CBHVAC* writes:

Indeed, the actual chlorine will be gone in a matter of days, leaving behind an alkaline NaOH solution that is its carrier, which promotes further growth. Worse than doing nothing!
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Actually, if there is no P or S trap, and the blower is located upstream from the condensate pan, the bleach can be pulled back into the pan, and the cholrine can damage the coil fins. Otherwise, its simply washed out.

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*CBHVAC* wrote:

The chlorine is poured into a condensation line at a point that has already exited the A/C housing. As far as I can tell, the condensation certainly is running away from the unit.
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*CBHVAC* writes:

Likely as much the NaOH as the chlorine. Most people don't know that the lye is what makes chlorine bleach clean things, not the chlorine.
The lye also stays around forever. Chlorine bleach loses most of the chlorine after a month or two. Keep it a year and you've got nothing but a lye solution.

The lye in chlorine bleach is moderately concentrated, and it will take a long time for condensate flow to dilute the pH back from the extreme alkalinity introduced by the bleach.
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