Pressure Relief Valve Required for Fire Pumps?

10/26/2018

When are pressure relief valves required for fire pumps, and what is their intended purpose? There's a wide variety of pump arrangements and many don't include pressure relief valves.

Posted anonymously by a member for discussion. Discuss this here.

3 Comments

MHK

10/29/2018 02:48:52 am

I think that one of the cases where a pressure relief valve is required is a fire pump system with a diesel engine driven fire pump. If a total of 121% of the diesel pump shutoff pressure plus maximum static pressure exceeds the system rating pressure, a pressure relief valve shall be provided.

WESLEY

10/29/2018 06:29:30 am

Agree with MHK from NFPA 20 (2013 Edition 4.18.1.2).

NFPA 20 also requires a pressure relief valve on electric variable speed limiting controllers when the churn pressure is higher than the rating of the system components (NFPA 20 2013 4.18.1.3).

Also addressed for Jockey Pumps where a centrifugal or turbine type is used and the shutoff pressure is higher than the rating of the system components (NFPA 20 2013 4.25.4.1).

We try to avoid exceeding 175 psi in a system to begin with but will use high-pressure pipe and components for portions that are exceeded. NFPA 20 (A.4.7.7) hasn't allowed the use of pressure relief valves to reduce pressure since 2003 for normal operation, but does permit pressure reducing valves (A.4.7.7.2).

10/30/2018 03:29:03 pm

Good topic, I was confused because I was blurring pressure relief and pressure reducing. Seams clear now.

Free Signup

Subscribe and learn something new each day:

Community

Thank You to Our Top August 2019 Contributors!

1. SK
2. Amr
3. SR
4. Jack
5. Mike

6. Jonathan
7. Nic
8. Wayne A.
9. Rusty S.
10. Brenton

Your Post

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

2019 PE Prep Guide
(Available Now!)

PE Prep Series
(Available Now!)

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 © 2019 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.