Periodic test of firefighting pump

[sinectica]

Hello guys,
we have a centrifugal horizontal pump for firefighting service in our plant. As far as I know we should periodically carry out tests on our pump in order to guarantee that it is in good condition.
What I would like to know is : which is the parameter I should verify in terms of flow-head of the pump? I think that we should see that on 150% rated flow the pump gives us more than the 65% rated head, but which head? total head or differential head?
The fact is that we have in our system a little more suction pressure than the one which has been supposed in the design then it is possible to reach more pressure at the discharge even if the pump is not like if it were new.

Finally, the procedure of this test is available in NFPA 25?

Thank you so much for your help,
Marc

 

[LCREP]

See NFPA 25, 2008 section 8.3. The pump should be started once a week for 10 minutes if electric and 30 minutes if diesel. If the pump is one that starts automatically by drop in pressure then it should be started that way each week.

Section 8.3.3 Annual flow test.

Test the pump at or near the NET pressure and flow at Churn or shut off pressure, pump rating @ 100% psi @ 100% gpm , and 65% of the psi @ 150 % rated flow. The pump flows and pressures should be with in 95% of the rated flow and pressure rating of the pump.

See this web site on how to graph the test results

http://cybermessageboard.fatcow.com/inspec4/viewtopic.php?t=145

http://www.inspector911.com/checklist/firepump/graphfirepumpresults.pdf

http://www.inspector911.com/checklist/fireflow/11 85 graph paper.pdf

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[LCREP]

Also if the pump is electric you should also record the volts and amps on each phase at Churn or shut off pressure, pump rating @ 100% psi @ 100% gpm , and 65% of the psi @ 150 % rated flow. Also record the rpm of the pump. I do not know where u are located but if in the USA most codes require a sprinkler contractor conduct the test.

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[LCREP]

Also check out this one day "hands on" fire pump seminar if you are in USA. It covers all of this and more.

http://www.chubb.com/businesses/service/chubb5935.pdf

http://www.chubb.com/businesses/service/chubb5954.html

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Fire Sprinklers Save Firefighters’ Lives Too!

 

[sinectica]

Thank you very much for your quick reply, it's been very useful. I'll check the sites you've mentioned in order to get further information.
When you say NET pressure, you mean then the pressure at the discharge of the pump (suction pressure+differential pressure)?
I am from Spain and here maybe it's not as easy to find this kind of information, again thank you so much!

Marc

 

[cdafd]

Do not know where you are located or if you fall under some gov. authority

BUT you r complete system should be inspected by a company that does annual inspections of fire protections systems.

If you want to do periodic inspections that is fantastic.

 

[LCREP]

When you say NET pressure, you mean then the pressure at the discharge of the pump (suction pressure+differential pressure)?


Yes discharge pressure minus suction pressure = net pressure. The pump rating MAY be on the pump IF it is a UL or FM listed pump. These ratings are what you are comparing the pump performance to each year.


****************************************
Fire Sprinklers Save Firefighters’ Lives Too!

 

[sinectica]

Thank you everybody for your comments, I've found a copy of NFPA 25 and I see that the parameters to be monitored are flow and net pressurre, the goal is to meet the pump requirements, not the system requirements (which take account the suction pressure).

Marc