• Welcome to The Building Code Forum

    Your premier resource for building code knowledge.

    This forum remains free to the public thanks to the generous support of our Sawhorse Members and Corporate Sponsors. Their contributions help keep this community thriving and accessible.

    Want enhanced access to expert discussions and exclusive features? Learn more about the benefits here.

    Ready to upgrade? Log in and upgrade now.

Condensate P-trap

Installation instructions usually have the manufacturers minimum requirements for the condensate ptrap and many times has pictures for the illiterate contractor
Click to expand...
Yes...and the depth of the seal is surprising sometimes....
 
I don't accept these running traps. To shallow. I have seen it specifically prohibited in some installation manuals
 
Alrighty then, The trap needs to hold 2" of water in order to overcome the negative pressure. So if the blower is upstream of the coil, no trap is required as there will be positive pressure at the coil. If the blower is downstream of the coil there will be negative pressure and a trap is required. The secondary drain will require a trap as well as the primary drain.

The only thing that I have been getting correct is the 2" seal. I have required a trap on every unit no matter where the blower is located. I haven't required a trap on the secondary drain. Well now I know better.
 
Last edited by a moderator:
Here's a job that wouldn't need a P-trap.



I was tempted to write a correction that said, "Gas connector is not permitted to be used as gas pipe.

 
I don't think it will work and the contractor is adamant that he has done this for years and I am the first inspector to reject it. Does anyone think that this will work?
Click to expand...
Just because you've done it that way for years does NOT mean that you've done it RIGHT for years.
 
Furnace looks like an upright and may not be permitted to be installed in this manner. I'd like to see a photo of the burners and flame direction? A-coil drain pan connection to drain?
 
Here's a job that wouldn't need a P-trap.

I was tempted to write a correction that said, "Gas connector is not permitted to be used as gas pipe.

Click to expand...
In theory, yes on positive side of the coil for furnaces but some of the manufactures instructions shipped with the coil state a P-trap is required and some will state no running traps. The new Trane AHU's with the coil on positive side state no trap is required. Also if you read the coil instructions some state the condensate line shall be insulated.
 
Our Mechanical Section has told me that the condensate drain from an evaporator coil is an indirect waste pipe.

Code: 
California Plumbing Code.
803.0 Indirect Waste Piping.
803.1 General. Except as hereinafter provided, the size and
construction of indirect waste piping shall be in accordance
with other sections of this code applicable to drainage and
vent piping. No vent from indirect waste piping shall
combine with a sewer-connected vent, but shall extend
separately to the outside air. Indirect waste pipes exceeding
5 feet (1524 mm), but less than 15 feet (4572 mm) in length
shall be directly trapped, but such traps need not be vented.
Indirect waste pipes less than 15 feet (4572 mm) in
length shall be not less than the diameter of the drain outlet
or tailpiece of the fixture, appliance, or equipment served,
and in no case less than 1⁄2 of an inch (15 mm). Angles and
changes of direction in such indirect waste pipes shall be
provided with cleanouts so as to permit flushing and
cleaning.
[/CODE]The part about the cleanouts is a hoot.

The secondary is exempt.



Could it be that the pipe is held on with tape?
 
Last edited by a moderator:
You must log in or register to reply here.
Back
Top