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NICET III - Fire Pump Practice Test Question

NICET III - Fire Pump Practice Test Question

NICET III - Fire Pump Practice Test Question

(OP)
These two questions have me stumped, if anyone can help me out or point me in the right direction, I would appreciate it!

1. A centrifugal pump is installed. It is rated at 100 psi at 1,000 gpm. After installation, testing indicates that the pump can flow 1,450 gpm at 60 psi.

Is the removal of this pump and the installation of another pump required by code?

a. No, it meets the 3rd point on the performance test.

b. No, the AHJ may accept failure to reach the 3rd point on the performance test if it meets the sprinkler demand

c. Yes, if demanded by the manufacture

d. Yes, NFPA 20 doesn’t permit and deviation from the field performance

- I think (b) per NFPA 20, 2016 edition. 14.1.1.3.1.

Where the maximum flow available from the water supply cannot provide a flow of 150 percent of the rated flow of the pump, the flushing flow rate shall be the greater of 100 percent of rated flow of the connected fire pump or the maximum flow demand of the fire protection system.

2. There is a 1,000-foot-long run of 6-inch schedule 40 pipe (C = 120). The fittings on this run of pipe have a total equivalent length of 80 feet. The end of this run needs to be able to provide 1,000 gpm at 60 psi. The evaluation at that location is 50 feet.

This run of pipe is to be supplied by a pump. The pump will be at an elevation of 5 feet and will draw from a surface level storage tank.

Which is the best pump to select?

a. 80psi @ 2,000gpm

b. 120psi @ 1,000gpm

c. 120psi @ 1250gpm

d. 175psi @ 1,000gpm

- I think (b)

60psi + 38psi for friction loss + 19.5psi for elevation loss = 117.5psi required @ pump discharge.

RE: NICET III - Fire Pump Practice Test Question

If the pump meets design demand its ok per NFPA 20 as you've stated.

I get the same answer as you for #2, 118 psi@ 1,000 gpm. The 120psi @ 1,000 gpm pump is the closest that is greater than the demand.

RE: NICET III - Fire Pump Practice Test Question

(OP)
Thank you MGXFP!

RE: NICET III - Fire Pump Practice Test Question

For #2, You have 1080 equivalent feet of 6" sch 40. The friction loss is ±38 psi. You have ±20 psi in elevation losses and you need 60 psi at the end. So yes, 120 psi at 1000 gpm is going to get you what you are looking for with those parameters.

Travis Mack, SET, RME-G,
MEPCad, Inc

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