×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Residual PSI at BOR and Main drain test

Residual PSI at BOR and Main drain test

Residual PSI at BOR and Main drain test

(OP)
Question: Does the main drain test and the residual psi at bor on the hydraulic data plate have any relation to each other?

RE: Residual PSI at BOR and Main drain test

Not necessarily. A main drain test in and of itself is pretty useless. My understanding is that it is a way to see if the water supply has been stable over the years or not. If you have steadily had 60 psi at the riser during main drain testing, then you all of a sudden see a 50 psi reading, then you have a problem in your water supply.

For comparing to the BOR info, it is not a great idea. If you have a light hazard system where the demand is 100 gpm and you do a full open main drain test where you may be flowing 200-400 gpm (just made up numbers), then your main drain test should have a lower residual than what is at the base of the riser requirement for the system.

Travis Mack
MFP Design, LLC
www.mfpdesign.com

RE: Residual PSI at BOR and Main drain test

A main drain test can also be used to check for obstructions. Example, I watched a main drain go from 80 static to 15 psi residual. Turns out the butterfly valve on the riser that had an indicator noting it was open, was actually about 80 closed. This was discovered when the contractor removed the valve. False sense of security. Same thing can happen on PIV,s and I have seen that as we'll.

RE: Residual PSI at BOR and Main drain test

To add to Sdpaddler50, such test can also detect if the shutoff valve on the supply line is fully opened or partially closed. A drain test test can also estimate the water supply adequacy for sprinkler systems as attested by insurance representatives periodically performing such tests of commercial properties.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources