I was under the impression that the soft start was more to reduce hammer on the electrical supply. Bruce is correct that a jockey pump(s) maintaining churn pressure on the systems would reduce the hammer; in a large volume system, we wouldn't expect as much hammer as in a short section of piping not up to churn pressure. A small surge suppressor of the bladder style might be a less costly answer if you are concerned about old underground whose integrity might be questionable, but if this is the case, additional testing of it might be prudent since without UG, you can't get water out of remote systems.\
glc -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Sunday, February 01, 2009 4:20 PM To: [email protected] Subject: Re: - prescriptions against soft-start pumps in NFPA water supplies.. Amongst the questions I would have is, would a soft start affect what hammer in a "large campus". I doubt much water is pumped during start up. I am envisioning a system with many thousands of feet of underground pipe. Wouldn't a jockey, or lower volume pump, that maintains pressure in the system higher than churn pressure of the fire pump be more effective? Yours, Bruce V. ----- Original Message ----- From: "å... ...." <[email protected]> To: [email protected] Sent: Sunday, February 1, 2009 2:40:22 AM GMT -08:00 US/Canada Pacific Subject: - prescriptions against soft-start pumps in NFPA water supplies.. NFPA 20 & 24 water supply pumps and supply systems. We have 3 large pumps drawings from a large reservoir. water supply is devoted to a campus of buildings. these are large volume pumps, redundant. Is there an NFPA requirement that these large pumps can NOT be soft start? We have predictions of water hammer, and wish to avoid this via soft start. scot deal excelsior fire engineering _______________________________________________ Sprinklerforum mailing list http://lists.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) _______________________________________________ Sprinklerforum mailing list http://lists.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) _______________________________________________ Sprinklerforum mailing list http://lists.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)
