Advice on locations of drum drip for a dry-loop system

[2civic3]

Hi guys,

I attached a sketch of the dry-loop system that I am working on. Its my first time working on a dry-loop system in a parking garage and need your help how to locate drum drip to this type of layout. Thanks in advance.

 

[cdafd]

Need to read 13, but thinking at low points or trapped areas

 

[cdafd]

https://dps.mn.gov/divisions/sfm/pr...Newleter/QR0911AuxiliaryDrains–Dry System.pdf

 

[2civic3]

cdafd: link don't work. thanks.

 

[cdafd]

https://dps.mn.gov/pages/Results.aspx?k=QR0911AuxiliaryDrains

Click on aux drain if link works

 

[2civic3]

Thanks. I already know this from NFPA 13. I just want someone to look at the sketch that I attached and give me an idea the locations of drum drip to a dry-loop system.

 

[cdafd]

I do not design, but more then likely a little hard without more info

 

[TravisMack]

That sketch does not provide enough information. What are the elevations of the piping? Where are the trapped sections? That is where the drum drips go. Are you talking about the remote inspector's test connection? If so, some where on the right hand side, near the bottom of the page off the remote branch line.



Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[2civic3]

@Travis:
-The pipe elev. is -57'-0" AFF (below grade), this is P6 parking level
-Trapped sections, that is what I want to know.

The client/customer is asking me the locations so that they can send to the electrician to set up the power for the electrical tracing.
You think you can give me your opinion the locations of the drum drips?

Thanks so much!!

 

[TravisMack]

Your plan does not indicate elevations of the piping. Do you have any offsets that cause for trapped sections of pipe? Do you understand what a trapped section is?

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[cdafd]

civic do you mind saying what you do for a living???

sounds like you are trying to do "heat trace" ?????

 

[mattyd723]

I just designed a very similar-looking dry loop system. There's really not enough info given but if my back was against the wall, I would recommend installing 2 drum drips: one on each of the mains that run east-west, at the half-way point between the mains that run north-south.

Are they planning on heat tracing the drum drips to prevent any collected condensation from freezing?

 

[mattyd723]

Here's a pictorial answer, in case my language wasn't clear:

Link

 

[jkampana]

In a dry system you have to slope the mains and branch lines to a point where it can be drained. Really, your drum drips could be anywhere on that plan as long as the pipes are sloped to those areas.

 

[jjmoore73]

Can you theoretically install everything level? If so, then you do not have any "trapped sections" per say; however, the entire system is trapped.
For dry systems, you have to install the branchlines pitched 1/2" per 10 feet so the water drains back to the main. Then the main has to pitch 1/4" per 10 feet back to a drum drip. To detemine where to put your drum drips, you have to figure how much vertical room you have between your high points and your low points. If you have 6" of vertical movement for your main, you can theortically have 240' of main sloped toward the the drum drip on one side, and 240' sloping to the drum drip on the other side. Watch were the main high-point and low point puts your outlet elevations for the branch lines. The main will be the branch line LOW POINT. At the main high point you'll need to make sure you have enough room at your branch line high point so the deflector is still below framing as required. At the main low point, make sure your branchline deflector isn't too far below the framing or you'll need a sprig. Not a big deal unless you fabbed the branch lines with 1/2" or 3/4" outlets. Based on this information, you can see your sketch is lacking the information needed to provide a solid location(s).

J. Moore
NICET III - Water Based