Tom, look at your conversion factor again. Bar X 14.5 = psi. Pump rating is 20 bar (290 psi), set point to start is 16 bar (232 psi).
You're saying there is a system pressure differential of 4 bar (58 psi) between normal daytime pressure and night time pressures? Apparently you don't have a jockey pump on the system to maintain the pressure? Any reason not to adjust the differential a bit wider, say drop the start point to 14 bar maybe? Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [email protected] http://www.ch2m.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of tom poisal Sent: Monday, May 03, 2010 3:18 PM To: [email protected] Subject: Re: Fire Pump On Mon, May 3, 2010 at 3:08 PM, sam b <[email protected]> wrote: > but do you expect this to go down so much ,more than 2 bars even,.? > am actually waiting for the status tonight...:) > > Yeah your talking 2 bars = only .1378 psi, I have seen systems lose 5-6 psi > overnight and gain it when the sun rises > > On Mon, May 3, 2010 at 11:02 PM, tom poisal <[email protected]> wrote: > > > sam, it is the temp rise/loss; when it gets to night time the water > cools > > and lowers the temp which lowers the psi/bar same with an overnight hydro > > test..not much you can do about it that i know. > > > > > > On Mon, May 3, 2010 at 2:57 PM, sam b <[email protected]> wrote: > > > > > Hii everyone > > > > > > > > > My previos mail in this forum was regarding a temporary fire pump(only > > > dieselPump) only. > > > we have installed this fire pump for temporary fire fighting in the > > site. > > > The pump is 500 USGpm @ 20 Bar.(NOn Listed).The risers we have > installed > > up > > > to 7 floors now. > > > The pressure switch setting is kept such that when presuure drops below > > 16 > > > Bar the pump automatically starts. > > > For the last 2 days we are seeing that the pump starts automatically at > > > night time.In the daytime there is no considerable pressure loss also. > > > our initial assesment was that it may due to air trapped inside ,as a > > > result > > > we installed air release valve in both risers .Also the NRV in the > > > pumpdiischarge was replaced to ensure there is no leakage. > > > > > > Any guesses on whtmay b the reason? > > > _______________________________________________ > > > 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]<to%[email protected]> > <to%[email protected]<to%[email protected]> > > > > <to%[email protected]<to%[email protected]> > <to%[email protected]<to%[email protected]> > > > > > > > > (Put the word unsubscribe in the subject field) > > > > > > > > > > > -- > > Tom Poisal, CET > > _______________________________________________ > > 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]<to%[email protected]> > <to%[email protected]<to%[email protected]> > > > > (Put the word unsubscribe in the subject field) > > > _______________________________________________ > 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]<to%[email protected]> > (Put the word unsubscribe in the subject field) > -- Tom Poisal, CET _______________________________________________ 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) _______________________________________________ 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)
