How to Calculate for Pipe Freezing/Heat Loss?

8/7/2019

Does anyone know which calculation can be applied (or if there is a calculator available) to determine if an insulated pipe will freeze (or how long it will take to freeze)?

We have a scenario where we specified a heat trace system to be used on branch lines extending from the building to an exposed exterior soffit that is subject to freezing conditions. Due to cost concerns, the school/contractor want to remove the heat trace and just insulate the pipe. Thanks.

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

8 Comments

Howard G. Gerber

8/7/2019 10:16:09 am

insulation only slows heat transfer, it does not stop it, given time the pipe will freeze. Install the heat trace. can you use a dry head in the soffit?

Douglas E. Colter

8/7/2019 12:29:16 pm

I have a resource publication from the American Society of Plumbing Engineers on pipe insulation and time-to-freeze calcs, reprinted from the 2012 Plumbing Engineering Design Guide Book. try www.ASPE.org

or send me an email and I will forward my copy.

Zachary Siegrist

8/8/2019 01:55:35 pm

Can you provide me a copy of the plumbing engineering design guidebook you referenced in the heat loss thread?

Steven Lopez

8/8/2019 11:39:51 am

They don't want to use a dry system for the exterior as it is intermittent. There are a few areas where branch lines extend to the exterior soffit.

Rusty Scott

8/7/2019 12:49:54 pm

I would give "nVent" Raychem commercial tech support 650-474-7709. They have a program called TraceCalc Pro2 that maybe can help. Their program may allow for you to see what would happen if the heat trace component was removed and insulation thickness is increased, I'm not sure it's worth a shot.

Howard G. Gerber

8/7/2019 12:58:56 pm

try this website:

https://www.wbdg.org/guides-specifications/mechanical-insulation-design-guide/design-objectives/time-freezing-fluid-insulated-pipe-calculator

Mike

8/7/2019 07:23:59 pm

Just one question.

Was this during design phase or construction phase?

Justin Stirling

8/9/2019 05:13:54 am

I was under the impression that there was not a UL/FM approved product on the market for branch line heat tracing (very similar situation with antifreeze solutions as well).

Has this changed?

Free Signup

Subscribe and learn something new each day:

Community

Thank You to Our Top
October '20 Contributors!

1. SK
2. Franck
3. Dan W.
4. Jonathan 5. Casey M.

6. Sean
7. Colin L.
8. Mike
9. Jonathan J
10. Daniel G.

Your Post

SUBMIT A QUESTION

The Toolkit

Sprinkler Designer or Engineer?

Get all of our tools, including the Sprinkler Database, Friction Loss Calculator, Fire Pump Analyzer and more:

FREE 30-DAY TRIAL

GET THE TOOLKIT

Filters

Exam Prep

2020 PE Prep Guide
(Available Now!)

PE Prep Series
(Available Now!)

2020 PE Prep Series
Current Leaderboard
(Click to enlarge)

PE Problems

Visit July-October for daily Fire Protection PE Exam sample questions.

Solutions are posted the day after posting.

Comment with your solutions, questions or clarifications.

Please note that questions posted are unofficial and in accordance with NCEES rules are intended to be similar to actual exam questions, not actual exam questions themselves.

RSS Feed

Home - About - Blog - Contact - Exam Prep - Store

Copyright © 2020 MeyerFire, LLC
The views, opinions, and information found on this site represent solely the author shown and do not represent the opinions of any other party, nor does the presented material assume responsibility for its use. Fire protection and life safety systems constitute a critical component for public health and safety and you should consult with a licensed professional for proper design and code adherence. Some (not all) outbound links on this website, such as Amazon links, are affiliate-based where we receive a commission for orders placed elsewhere.