Great points Mike.  The newer (and more expensive equipment) do offer some options as long as the AHJ approves their use. 

Keep in mind, a fire pump system is designed to run to destruction if it is needed to. This includes a low pressure suction condition. 

Thanks,

John


John August Denhardt, P.E

Vice President Engineering and Technical Services
American Fire Sprinkler Association
301-343-1457

Are you a member with a technical question? 

Don't forget one of the most valuable resources that AFSA provides is Technical Reviews by our Technical Services Department. It’s like having an FPE on your staff. Visit www.firesprinkler.org/technicalreview to submit a question today! (Member login required.)  


On Jan 6, 2026, at 08:13, Mike Morey <[email protected]> wrote:



In fairness, there are a couple other options today, most controllers now can be configured for a low suction shutoff if allowed by the AHJ (however this is rarely an acceptable option) and pressure limiting drive (PLD) diesels can have a low suction throttle in their controller (this is becoming pretty common as the added transducer and controls are typically cheaper than the valve, and you aren’t adding loss etc).  But typically, when someone says “low suction alarm” it’s just as you say, a buzzer/supervisory signal and no action is taken by the controller.

 

Mike Morey

2025 NFSA Top Tech Champion NICET IV CFPS

Project Estimator • Fire Protection Group
Shambaugh & Son, LP
an EMCOR Company

7614 Opportunity Drive • Fort Wayne, IN • 46825

direct 260.487.7824 /  cell 260.417.0625
email
[email protected]
24/7 SERVICE LINE 888.217.7055

<image001.png>

 

From: John Denhardt <[email protected]>
Sent: Tuesday, January 6, 2026 7:42 AM
To: [email protected]
Subject: [Sprinklerforum] Re: LOW SUCTION PRESSURE

 

Low suction alarm? Low suction valve? A low pressure alarm is just an alarm or supervisory alarm. No impact to the fire pump system as it will run to destruction. A low suction valve will restrict the discharge to limit water flow rate to prevent

ZjQcmQRYFpfptBannerStart

This Message Is From an External Sender

This message originated outside your organization.

ZjQcmQRYFpfptBannerEnd

Low suction alarm?  Low suction valve?

 

A low pressure alarm is just an alarm or supervisory alarm. No impact to the fire pump system as it will run to destruction. 

 

A low suction valve will restrict the discharge to limit water flow rate to prevent a low suction situation. The fire pump system (including a diesel driver) will only see lesser water flow. 

 

I hope this helps. Feel free to call me to discuss further. 

 

Thanks,

John

 

John August Denhardt, P.E

Vice President Engineering and Technical Services

American Fire Sprinkler Association

301-343-1457



Are you a member with a technical question? 

Don't forget one of the most valuable resources that AFSA provides is Technical Reviews by our Technical Services Department. It’s like having an FPE on your staff. Visit www.firesprinkler.org/technicalreview to submit a question today! (Member login required.)  


On Jan 6, 2026, at 07:33, [email protected] wrote:


_________________________________________________________
SprinklerForum mailing list:
https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org
To unsubscribe send an email to [email protected]

Does a low suction pressure alarm have any affect on the diesel fire pump’s engine control?

This message is for the named person's use only. It may contain confidential, proprietary or legally privileged information. No confidentiality or privilege is waived or lost by any mistransmission. If you receive this message in error, please immediately delete it and all copies of it from your system, destroy any hard copies of it and notify the sender. You must not, directly or indirectly, use, disclose, distribute, print, or copy any part of this message if you are not the intended recipient.

_________________________________________________________
SprinklerForum mailing list:
https://url.usb.m.mimecastprotect.com/s/32rnCVJz8Bt15QN8ukuvHE-k5t?domain=lists.firesprinkler.org
To unsubscribe send an email to [email protected]
_________________________________________________________
SprinklerForum mailing list:
https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org
To unsubscribe send an email to [email protected]

Reply via email to