Thread: Primary Drain Line

Is it acceptable to dump the primary drain line into the vent? I say no. See arrow in photo.

Similar Threads:

• Unusual Air and Noise from Bath Sink - AC primary drain
• Float switch for primary A/C drain?
• Primary drain line
• AC Primary drain vent
• Primary drain line material

Originally Posted by brianmiller

Is it acceptable to dump the primary drain line into the vent? I say no. See arrow in photo.

Your photo cut off, but no the AC cannot discharge into a plumbing vent.

M1411.3 Condensate disposal.
Condensate from all cooling coils or evaporators shall be conveyed from the drain pan outlet to an approved place of disposal. Such piping shall maintain a minimum horizontal slope in the direction of discharge of not less than ¹/₈ unit vertical in 12 units horizontal (1-percent slope). Condensate shall not discharge into a street, alley or other areas where it would cause a nuisance.

No. It must be to an indirect connection and a trap must be employed to prevent sewer gas from entering the HVAC. That installation stinks, literally.

What is/are the "Approved" place(s) of disposal?
The code does not say.

A trap should be installed on the drain line at the appliance.
A second trap would not be approved.

Like Jim, I think that an air gap with a 2nd trap is best
But is it not to code?

Originally Posted by Rick Cantrell

What is/are the "Approved" place(s) of disposal?
The code does not say.

A trap should be installed on the drain line at the appliance.
A second trap would not be approved.

Like Jim, I think that an air gap with a 2nd trap is best
But is it not to code?

OK I'll bite.

Just what code, Manufactures Instructions or Best Practice would allow anything ( not just AC ) to discharge into a Plumbing Vent Stack ?

Originally Posted by Billy Stephens

OK I'll bite.

Just what code, Manufactures Instructions or Best Practice would allow anything ( not just AC ) to discharge into a Plumbing Vent Stack ?

It wasn't so much a challenge as it is a question.
What is an " approved place of disposal"?

Originally Posted by Rick Cantrell

It wasn't so much a challenge as it is a question.
What is an " approved place of disposal"?

Ask your AHJ.
* the vent stack would not be one of those.

Originally Posted by Billy Stephens

Ask your AHJ.
* the vent stack would not be one of those.

As a kid, when I would ask my Mom-ma something like that, she would say "Because I said so".

Originally Posted by Rick Cantrell

As a kid, when I would ask my Mom-ma something like that, she would say "Because I said so".

I just posted The Code M1411.3 I don't Make The Code or have Authority to Interpret The Code. Your locale AHJ can give you your " Approved Places."

* gave ya Mon-ma lots of headaches did ya?
** did she pay to get you to Go Away ?
*** here be Da Cek.

After re-reading Jim's response I see that he did say "indirect".
(Which is what I was describing.)
But I'm still not sure that, as it is shown, it is not allowed.

Originally Posted by Rick Cantrell

But I'm still not sure that, as it is shown, it is not allowed.

Great Show Me How it Could be Allowed.

Originally Posted by Billy Stephens

* gave ya Mon-ma lots of headaches did ya?

Well, now that you mention it

Originally Posted by Billy Stephens

** did she pay to get you to Go Away ?
*** here be Da Cek.

Now your just making me feel guilty
Think I'll call momma up and tell her I love her.
She deserves it.

The real answer will come from the AHJ. In most cases I have seen condensate tie into vent lines and the inspector doesn't make an issue of it.

IF you provide a trap in the attic it will freeze in the winter. If you are using a condensing furnace in the attic you'll have other freezing issues as well.

Originally Posted by Billy Stephens

OK I'll bite.

Just what code, Manufactures Instructions or Best Practice would allow anything ( not just AC ) to discharge into a Plumbing Vent Stack ?

It seems somewhat obvious the OP's pic is in an attic, and I'll assume highest level upstream side of the structure's/building's sewer.

A CW&V system. Nothing to indicate other than just mechanicals in what appears to be the highest level/story of the structure (occupied attic) the wet vent may be dedicated solely for this purpose. Incorrectly altered/repaired but appears to NOT have been (originally) a dry-vent to begin with.

Cruddy pic somewhat out of focus and doesn't show much other than incorrect fittings upside down in the OP, just addressing a wet vent in a combination waste (or drainage) & vent system.

FYI most of the SW states did or do use UPC and UMC based code not IPC/IMC regarding same.

Bottom line - not all venting is "dry" throughout, such as a combined waste & vent (wet vent), and there is no indication that the pictured is actually "attached" to the sanitary system and not some other such as gray system or indirectly discharging elsewhere below for that matter.

Originally Posted by H.G. Watson, Sr.

It seems somewhat obvious the OP's pic is in an attic, and I'll assume highest level upstream side of the structure's/building's sewer.

A CW&V system. Nothing to indicate other than just mechanicals in what appears to be the highest level/story of the structure (occupied attic) the wet vent may be dedicated solely for this purpose. Incorrectly altered/repaired but appears to NOT have been (originally) a dry-vent to begin with.

Cruddy pic somewhat out of focus and doesn't show much other than incorrect fittings upside down in the OP, just addressing a wet vent in a combination waste (or drainage) & vent system.

FYI most of the SW states did or do use UPC and UMC based code not IPC/IMC regarding same.

Bottom line - not all venting is "dry" throughout, such as a combined waste & vent (wet vent), and there is no indication that the pictured is actually "attached" to the sanitary system and not some other such as gray system or indirectly discharging elsewhere below for that matter.

FYI
Bottom Line take da money.

Originally Posted by Billy Stephens

OK I'll bite.Just what code, Manufactures Instructions or Best Practice would allow anything ( not just AC ) to discharge into a Plumbing Vent Stack ?

That's not a "plumbing 'vent stack'", although there is a portion designated to "dry vent"-ing.

As far as your general assertions/challenges for your own area, see ('09) IPC Ch. 2, Sect 202 (definitions) and Ch. 9, Sects. 908 (.1 & .3), 909 & 912.

We cannot see behind the panel - therefore there is no conclusive evidence nor assertion by the OP that the connection from the condensate drain pan is anything other than indirect; it appears obvious it is above the trap weir.

Despite the obvious indications that there are other problems at issue in this area, the concerns do not include as you represent.
There is no indication that the assending (dry) vent pipe from the indirect waste piping combines with any sewer-connected vent, and that it does not extend separately to the outside air. Both wet vented 'fixtures' are within the same story/building level (attic, occupied and apparently at least partially may/could be "habital" attic).


Why are you writing checks again??

Originally Posted by H.G. Watson, Sr.

That's not a "plumbing 'vent stack'", although there is a portion designated to "dry vent"-ing.As far as your general assertions/challenges for your own area, see ('09) IPC Ch. 2, Sect 202 (definitions) and Ch. 9, Sects. 908 (.1 & .3), 909 & 912We cannot see behind the panel - therefore there is no conclusive evidence nor assertion by the OP that the connection to the condensate drain pan is anything other than indirect, it appears obvious it is above the trap weir.Despite the obvious indications that there are other problems at issue, not as you represent.You writing checks again??

How do you know what's show is not a Plumbing Vent ? Dry or Wet ?

* You still doing the Drive Thru ?

Originally Posted by Billy Stephens

How do you know what's show is not a Plumbing Vent ? Dry or Wet ?

* You still doing the Drive Thru ?

I did not say THAT.

Is not "plumbing vent STACK" as only YOU have asserted.

You're delving into peck-ish word-smithing & twisting, and you haven't the skill set to pull it off.


I have already provided the information for YOU to learn why YOUR statements are completely erroneous. I responded to your challenges/demands with the information and the OP has provided three additional photos beyond the originally posted one.

Originally Posted by H.G. Watson, Sr.

I did not say THAT.

Is not "plumbing vent STACK" as only YOU have asserted.

You're delving into peck-ish word-smithing & twisting, and you haven't the skill set to pull it off.


I have already provided the information for YOU to learn why YOUR statements are completely erroneous. I responded to your challenges/demands with the information and the OP has provided three additional photos beyond the originally posted one.

So you know by the posted photo and can attest what's shown is not a Plumbing Vent Stack?
*the only thing you have provided is further evidence of the world according to H.G.