Todd, You might try checking when the jockey pump turns on & off, if the fire pump uses a mercoid pressure differential switch it may not be sensitive at very low pressures. Also someone should check the fire pump will start in a manual mode, and the pressure at static conditions. Make sure that the pressure switch is the correct for the pressure range, here is the link to Mercoid: http://www.mercoid.com/pressure.html
Hope this helps. Yours truly, FRANK J. HERRICK CITY OF LEAWOOD FIRE DEPARTMENT OFFICE OF THE FIRE MARSHAL -----Original Message----- From: Todd Williams [mailto:[email protected]] Sent: Monday, November 02, 2009 10:07 AM To: [email protected] Subject: pump failure/flow alarm A situation came up this morning that I probably should know the answer to, but I don't. A building is protected by a 500 gpm at 40 psi diesel pump taking suction from a tank (no public water). The pump feeds to 2 sprinkler risers with riser checks and flow switches. The jockey pump pressure is set to approximately 50 psi. If the inspector's test opens and the pump does not turn on, there is not enough flow in the system to activate the flow switch. Consequently, if a sprinkler goes off and the pump does not activate, then no alarm is sent. Having never run into this or heard of it being tested, I don't know if this is normal but it seems like it shouldn't be. Is this normal? Is it ever tested? My first reaction is what is the delay on the flow switch set to (30 seconds). I told them to set to delay to 0 and see what happens. It may be just a situation of getting the setting right. Thoughts? Todd G. Williams, PE Fire Protection Design/Consulting Stonington, Connecticut www.fpdc.com 860.535.2080 _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
