Usually, the fire pump is diagnosed during the maintenance process. The diagnosis of the fire pump failure is a key. Several common faults and elimination measures are given
below for the purpose of the fire pump fault diagnosis.
1) No liquid supply, insufficient liquid supply or insufficient pressure. The pump is not filled with water or is not properly vented
Measure: Check that the pump casing and inlet lines are all filled with liquid.
2) The speed is too low
Measure: Check if the motor wiring is correct, the voltage is normal or the turbine pressure is normal.
3) The system head is too high
Measure: Check the head of the system (especially the friction loss).
4) Pipeline pump suction is too high
Measure: Check the existing net head (too small or too long inlet line will cause a large friction loss).
5) Impeller or pipeline is blocked
Measure: Check for obstacles.
6) The direction of rotation is wrong
Measure: Check the direction of rotation.
7) There is air leakage in the inlet line
Measure: Check if the inlet line have air pockets or air leaks.
8) The packing or seal in the stuffing box is worn out, causing air to leak into the pump casing.
Measure: Check the packing or seal and replace as needed, check if the lubrication is normal.
9) Insufficient suction head when pumping hot or volatile liquids
Measure: Increase the suction head and consult the manufacturer.
10) The bottom valve is too small
Measure: Install the correct-size bottom valve.
11) The bottom valve or inlet tube is not deep enough
Measure: Consult the manufacturer for the correct immersion depth. Use a baffle to eliminate eddy currents
12) The impeller clearance is too large
Measure: Check if the gap is correct.
13) Impeller damage
Measure: Check the impeller and replace it as required.
14) The impeller diameter is too small
Measure: Consult the manufacturer for the correct impeller diameter.
15) Pressure gauge position is incorrect
Measure: Check if the position is correct and check the outlet nozzle or pipe.