Cracked HVAC Condensate Pan

[GoingMyWay]

Anyone have any suggestions for how I can fill this crack in the threaded portion of the condensate pan in our HVAC?  I initially thought about using CA glue, but then figured that would likely break as soon as I screwed the drain line back in.  100% silicone might be the best bet, but I fear it will be messy.  In that scenario, I planned on squeezing in the silicone and then immediately screwing the drain line back in - I'm not sure I'll be able to unscrew the drain line after that though. 

I guess alternatively I could squeeze in the caulking and try to wipe off any excess and then let it cure before screwing the drain line back in?  I'd be a little concerned that the threads would be all filled up with silicone so it might not screw in anymore?

I just took a closer look at the picture I took and I suppose it's most important that whatever I use, I try to apply it as far back as possible.

Replacing the entire condensate pan isn't really feasible as I believe that would require having an HVAC tech come out and would require refrigerant recovery, cutting, brazing, etc.

Anyone have any thoughts or suggestions?

 

[rvieceli]

[member=66216]GoingMyWay[/member]  it appears that there are two of those connections in that pan. One being blocked by the plug on the right. Is that the case? Does the plugged hole go to the same thing. If so you might be able to remove the plug, check the threads there and use that hole for the actual drain line. Then silicone the crap out of the other threaded hole and the plug and thread the plug into that one.

Ron

 

[GoingMyWay]

That's a great observation and suggestion!

I think the plugged hole does the same thing, though I'm not exactly sure why it's plugged.  The only thing I could think of is that it appears that the current drain port is ever so slightly lower than the plugged port.  I wonder if drainage might be an issue with the slightly higher port?

 

[Sparktrician]

[member=66216]GoingMyWay[/member], I'd add one thing to what [member=3192]rvieceli[/member] said - figure out what stress caused that fitting to crack FIRST.  I suspect that the drain line was too short and the installer forced the pipe over and held it in place as the glue set up.  Over time, vibration and pulling stress may have been the cause of the crack.  If you can, plug and silicone the cracked fitting as suggested, then re-do the drain line to mate with the other fitting, but this time, cut the PVC so that it's not stressed and has an appropriate slope.  That, and don't over-tighten the screw-in fitting.  [smile]

 

[RKA]

The lower port is the primary drain.  It was likely over torqued and cracked judging by how little Teflon tape remains on the male fitting.  The second higher port is the secondary drain intended to direct water somewhere obvious so you know the primary is plugged and needs to be serviced.  Without the secondary you can get water overflowing into the airhandler and furnace or your plenum and duct work.  If it’s in the attic, it may eventually drip through your ceiling as well, so a giant mess.

You can use the secondary, but make it an annual ritual to clean that secondary port and the drain lines once or twice a year.  I would also add an audible alarm in the secondary pan below the unit so you have an additional warning that there is a problem.  If you sell your house, expect the home inspector to flag this.

 

[Holzhacker]

The cracked opening is the primary drain hole; the plugged one the secondary. You can use either. The water coming out isn't pressurized. Caulk the crack, caulk the male adapter both with good clear silicone caulk, ease the male adapter secure and it probably won't leak until after you are gone.
If you want an alarm go to HD, they sell the 'watchdog' alarm in the plumbing aisle. If it gets hit with water it screams like a 2 year old that just had its candy taken away.

 

[GoingMyWay]

[member=66216]GoingMyWay[/member], I'd add one thing to what [member=3192]rvieceli[/member] said - figure out what stress caused that fitting to crack FIRST.  I suspect that the drain line was too short and the installer forced the pipe over and held it in place as the glue set up.  Over time, vibration and pulling stress may have been the cause of the crack.  If you can, plug and silicone the cracked fitting as suggested, then re-do the drain line to mate with the other fitting, but this time, cut the PVC so that it's not stressed and has an appropriate slope.  That, and don't over-tighten the screw-in fitting.  [smile]

The pan was fine until I had to have the A coil replaced back in 2011.  The condensate line had to be cut and the PVC was unscrewed (it was originally 1 piece and all glued together when the unit was originally installed).  I think it was likely screwed in too tightly when it was reinstalled.  A coupling (standard glued coupling) was then used to reconnect the pipes.  I don't think it's an issue of the pipe being too short - there is a lot of play in the the rest of the drain line.  I ordered this coupling to reassembly the pieces.  This will allow me to disassemble everything in the future without needing to cut the pipes again.  I also bought another standard coupling and a short piece of 3/4" PVC pipe in case I need to make it a little bit longer.

The lower port is the primary drain.  It was likely over torqued and cracked judging by how little Teflon tape remains on the male fitting.  The second higher port is the secondary drain intended to direct water somewhere obvious so you know the primary is plugged and needs to be serviced.  Without the secondary you can get water overflowing into the airhandler and furnace or your plenum and duct work.  If it’s in the attic, it may eventually drip through your ceiling as well, so a giant mess.

You can use the secondary, but make it an annual ritual to clean that secondary port and the drain lines once or twice a year.  I would also add an audible alarm in the secondary pan below the unit so you have an additional warning that there is a problem.  If you sell your house, expect the home inspector to flag this.

There is actually a floor pan (fortunately) and a water sensor that kills the unit when water is detected.  I had moved the sensor out of the pan because it shut off from a little bit of water in the pan (I was totally bypassing the intended safeguard  :-[).  I completely forgot about it and the pan ended up filling up with quite a bit of water.  It looks like a little bit of water is in fact running into the plenum right now.  I used some aluminum foil to direct the water down into a cup in the floor pan.  I tried looking inside of the plenum with a borescope that I have, but I really couldn't see much inside.  I guess that's a good thing.

The cracked opening is the primary drain hole; the plugged one the secondary. You can use either. The water coming out isn't pressurized. Caulk the crack, caulk the male adapter both with good clear silicone caulk, ease the male adapter secure and it probably won't leak until after you are gone.
If you want an alarm go to HD, they sell the 'watchdog' alarm in the plumbing aisle. If it gets hit with water it screams like a 2 year old that just had its candy taken away.

I guess I should just continue using the primary drain hole then and just caulk the heck out of it?  It probably won't be possible to unscrew again it if everything is caulked together right?

 

[Sparktrician]

As long as you're rebuilding things, you might want to consider adding in a trap which will allow you to monitor the drain. 

 

[RKA]

Great suggestion!  I just had new hvacs installed 2 months ago (along with replacing water damaged insulation and sheathing in my attic) and they put those traps in.  I saw them and instantly thought ...  [doh].  Why did it take them so long to invent a clear pipe so you can see that it needs to be cleared!

 

[GoingMyWay]

There is already a trap that's been bent into the drain line with an access port on top, but it's not clear.

I actually thought there might have been a blockage in the line that was upstream from the trap, but I couldn't really see anything until I cut the pipe.

I probably should have taken a picture of how everything looked before I cut the PVC, but the pictures below show how it looked like.

 

[Cheese]

Then silicone the crap out of the other threaded hole and the plug and thread the plug into that one.

Ron

I’d do a variation of what Ron suggested. But instead of inserting a plug into the damaged hole, just insert another male to female adapter and you can then continue to use the primary port as intended. You could even substitute a brass adapter for the pvc adapter to make sure the cracked housing will never happen again.
I’d also think about incorporating the clear trap for a visual alarm. I like that idea.  [smile]

 

[GoingMyWay]

Thanks for the advice and suggestions.

I liberally applied the silicone to the inside of the pan, the interior crack and threads, as well as to the threads on the male fitting.  I glued on a PVC coupling fitting with some PVC pipe to make up the difference where the old coupling had been cut out.  I used a flexible connector to make the final connection so that I can disassemble things again in the future without needing to cut anything.

Everything has been put back together again.

Hopefully she's watertight and seaworthy once again (I didn't test).

This was actually my first time using PVC primer and glue.  I have only seen it being applied on TV and on YouTube.  I made a mess with the PVC primer.  I read that since this isn't pressurized that I probably could have even skipped the primer, heck it's only a condensate drain line - I bet the friction fit between the PVC fitting would have been good enough anyway.

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[RKA]

You can't rely on the friction fit, vibrations from the unit cycling will loosen it over time.  You need to glue it, so good job!  Hopefully that stays water tight.  The only concern I would have is if that fitting was torqued too much and it opened the crack enough that the caulk couldn't make up the gap.  It wouldn't take much, but test it next spring on a hot and humid day and hopefully it's all good.

 

[GoingMyWay]

Not sure if you can see from the picture or not, but I did use a Sharpie to mark the depth of the male fitting before I applied the silicone.  There's no guarantee that I hadn't over torqued it when I did my dry fit, but I did at least have some frame of reference to go off to make sure I didn't go crazy when I screwed it back in with the silicone.

The whole leaking thing was kinda weird.  The crack has presumably been there since 2011, but the condensate wouldn't always leak out and down into the drip pan on the floor. In fact it was quite rare.  It seems like the conditions had to be exactly right (high enough humidity and temperature and having the AC run for a certain amount of time) for the water to actually leak out.