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Title says it all. New installation. Almost looks like there isn’t enough offset in the pipe to create a seal, but more basically I wonder if this type of running trap meets code.
I’m no hvac guy but I have to wonder why you need a trap when going in to a condensate pump?
 

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Need to know if it is a negitive or postive pressure system (at the coil) and the stactic pressure of the duct system.

In a positive pressure system an incorrect trap will just cause pressurized air to dishcharge from the vent. In a negitive pressure system an improper trap can all kinds of water related issues.

nickko,

The trap in a condensate line serves a different purpose than in a plumbing system.

Tom
 

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Looks like it's a negative
If that's the case the trap is probably not tall enough. The distance from the bottom of the drain pan pipe to the bottom of the horizontial line bottom past the trap needs to be 1" for every inch of negitive static duct pressure plus 1". The weir needs to be half that height.

Tom
 

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If that's the case the trap is probably not tall enough. The distance from the bottom of the drain pan pipe to the bottom of the horizontial line bottom past the trap needs to be 1" for every inch of negitive static duct pressure plus 1". The weir needs to be half that height.

Tom
Hard to say from that picture since it’s snapped on an angle, look from a steep enough angle and it will look like a straight pipe.
 

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It's compliant in tx. I install a capped clean out line next to it to get to the material that eventually accumulates in it.
 

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Discussion Starter #10
Sefi ... there is a T just to the left of the trap.

Tom ... how do you determine if its positive or negative pressure?
 

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Sefi ... there is a T just to the left of the trap.

Tom ... how do you determine if its positive or negative pressure?
Location of the blower. A positive pressure system blows the air through the coil, negative systems draw the air through the coil.

A negative system can easily draw the trap dry if it is not designed properly. This can cause all kinds of moisture problems.

On a positive system, biggest issue is the air leak, the blower just pushes the water out of the trap.

Duct pressure is an important factor as to the traps function.

Tom
 

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Need to know if it is a negitive or postive pressure system (at the coil) and the stactic pressure of the duct system.

In a positive pressure system an incorrect trap will just cause pressurized air to dishcharge from the vent. In a negitive pressure system an improper trap can all kinds of water related issues.

nickko,

The trap in a condensate line serves a different purpose than in a plumbing system.

Tom
Thanks tjbnwi.
I did not know that about an vac trap.
 

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If the bottom of the inside of the pipe in the straight sections is higher than the top of the loop on the inside of the pipe it will make the seal. There should be some extra there for a cushion for evaporation.

I never understood why it was needed myself. I still put it on my shop AC

 

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If the bottom of the inside of the pipe in the straight sections is higher than the top of the loop on the inside of the pipe it will make the seal. There should be some extra there for a cushion for evaporation.

I never understood why it was needed myself. I still put it on my shop AC

What did you use to make the copper connections? Braze, solder or that loctite looking stuff?
 

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I didn't do it. I had a pro come in and connect the compressor and A Coil. He brazed everything.

Close of a pic I got. Black insulation goo all over it anyway.

 

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That's not how they do it here. Need a real trap (not a "running trap") with clean-out access, even if it goes right to the condensate pump.

I still wonder why the big box stores don't sell them. And that's probably why they installed the running trap.. it's on the shelf.

That capped tee is "less than functional", too.
 

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Definitely need clean out access. Had to do mine this year, wood flour dust sediment and water make for wood mud. Guess my filters aren't perfect
 

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That's not how they do it here. Need a real trap (not a "running trap") with clean-out access, even if it goes right to the condensate pump.

I still wonder why the big box stores don't sell them. And that's probably why they installed the running trap.. it's on the shelf.

That capped tee is "less than functional", too.
The one in Leo's shop is 4-45º bends and pipe.

What they going to sell? A properly sized trap is figured by a formula that involves knowing the static pressure of the duct system.

Tom
 
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