HVAC Condensation pipe clogged?

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MichMich

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Hello there!
So my HVAC system is in the attic.
There is a tray (For condensation, with the outflow to the outside of the house). And there is a main condensation outflow pipe that goes down to to nearest bathroom (sink).
Looks like the main one is clogged?
My tray keeps filling up and water drains outside. I've poured half gallon of vinegar with hot water in there. Didn't help.
Perhaps some other ideas?
I don't have a compressor. And I'm not that handy with tools. Yet, I'm opened to suggestions.
Thanks!
Mike
 

Jeff Handy

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Show some pics of the connection down at the sink.

And also pics of the outlet in the collection tray that leads to the line going to the sink.

A wet vac might be able to suck out the blockage, or blow it out.

You can cobble together an adapter to fit any opening or fitting.
 

Jeff Handy

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Is the drain on the lower left the primary drain or the backup drain?

And where in the picture is the other drain?
 

MichMich

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The one on the left 3/4" is the overflow from the tray. The one in right bottom corner is the one with t, the main one, where I've poured hot water and vinegar. This one I'm sure goes to the bathroom below.
 

Jeff Handy

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First of all, you are not fully answering questions.
Read posts more carefully, and please answer specifically.

I would take that clamp off from the sink drain tailpiece, with a pan under it to catch any leakage.

Then I would adapt a shop vac or leaf blower to that hose, and try to blow it clear.

EDIT Thanks for adding those new details to your post.
 

Jeff Handy

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There is also a little condensate trap inside the furnace, usually it has a short section of flex hose after it, which then leads to the pvc condensate drain attached to the outside of the furnace.

Usually this trap looks like a rectangular white box, about as big as a deck of cards.

These traps are often prone to plugging up.

When the trap gets plugged, the condensate can’t get out into the condensate drain line, so it quickly overflows the small internal catch pan inside the furnace.

Then it runs into the bigger backup catch pan that is taking your condensate now.

If you blow the drain line clear from the sink, that should blow the trap clear also.
You might have to temporarily cap that opening in the pvc on the far right.

Just wrap a baggie over it, doubled up and secured with duct tape.

That will also keep yucky stuff from spraying out of there.

I have a client with three furnaces, and I have to blow the condensate traps clear every month or two, or else they plug up and flood.
 

Jeff Handy

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If you are a manly man, you can also just put your mouth on the flex hose under the sink, and give several good long vigorous puffs into it.

Watch out for sudden leakage after you blow.
And be sure to temporarily cap off the opening I mentioned earlier, above the pvc tee.
 

MichMich

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I'll probably connect the shop vac in the bathroom. And suck whatever is there. Water. Goo.
Thinking also about getting the brush on the wire to stick it into t trap to mechanically push thru any of the more solid goo.
 

Jeff Handy

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Don’t stick anything into the trap inside the furnace.

Cleaning out the sink trap is a good idea.

But you also need to blow air into the furnace trap, in case that is the source of the overflow problem.

Or have your hvac service change the trap and clean out the internal drain lines.
 

Twowaxhack

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Put the cap back on the drain line at the unit.

Take the line apart at the tee under the lavatory and use a shop vac to suck the line clear. Make sure the tee is open to the lavatory drain as well.

If that doesn’t clear it then call an AC guy.
 

MichMich

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Put the cap back on the drain line at the unit.

Take the line apart at the tee under the lavatory and use a shop vac to suck the line clear. Make sure the tee is open to the lavatory drain as well.

If that doesn’t clear it then call an AC guy.
put the cap back on the line on the right bottom? Circled the cap and line it covers
 

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Twowaxhack

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put the cap back on the line on the right bottom? Circled the cap and line it covers
Yes, that way you create suction with the shop vac all the way into the unit.

The trap at the unit will need to prime again. If water is not in the trap at the unit it can leak a little until it primes.

The negative pressure of the unit will pull air through the trap and it can leak a little until it primes.
 

MollyM99

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Greetings! I would like to see more pictures of your problem. It is worth finding as many buckets as possible and putting them in the bathroom so that water flows there before the arrival of specialists. I also recommend that you tighten all adapters to keep water out. In the future, move the air conditioning system from the attic to the outside of the house. I recommend that you read more about all these methods here - . I wish you to solve the problem as soon as possible! Good luck!
 
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JG plumbing

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Just fyi that drain shouldn't be hooked to your tail piece like that. You need an air gap.
 

Twowaxhack

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Just fyi that drain shouldn't be hooked to your tail piece like that. You need an air gap.
It’s similar to a high loop dishwasher drain rather than a air gap mounted on the sink in the sense that theres no way for the lavatory to back up into the unit because the AC unit is in the attic.

The unit in the attic has a secondary emergency drain pan if it’s primary gets clogged.

Is it to code ? Nope, but that doesn’t matter in this case.

It may have been approved at the time it was built.
 

JG plumbing

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It’s similar to a high loop dishwasher drain rather than a air gap mounted on the sink in the sense that theres no way for the lavatory to back up into the unit because the AC unit is in the attic.

The unit in the attic has a secondary emergency drain pan if it’s primary gets clogged.

Is it to code ? Nope, but that doesn’t matter in this case.

It may have been approved at the time it was built.
No I get it. Bacteria don't care.
 
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