Generally speaking, in the process of servicing fire pump, fault diagnosis of fire pump is an important link. There are several common faults and eliminating measures for you to diagnose faults for fire pump effectively.

1. No liquid, insufficient liquid supply and pressure

1) Pump hasn't infused water or it doesn't exhaust properly

Eliminating measures: Check if pump case and source line are full of water.

2) Too slow speed

Eliminating measures: Check wiring of electrical machinery to make sure whether voltage and steam pressure are normal or not.

3) Too high system head

Eliminating measures: Check system head( especially

frictional loss)

4) Too high suction

Eliminating measures: Check the present net pressure head

5) Impeller and pipeline get blocked

Eliminating measures: Check if there is any barrier.

6) Wrong rotational direction

Eliminating measures: Check direction of rotation

7) Producing air or the source line is leaking

Eliminating measures: Check if source line has cavitations or air leak

8) Air get into pump case because padding in stuffing box or seal wear

Eliminating measures: Check padding and seal to make sure if they need to be changed, and check if lubrication is normal.

9) Insufficient suction head when pumping hot or volatile liquid

Eliminating measures: Enlarge suction head and consult manufacturers about it.

10) Bottom valve is too small

Eliminating measures: Install the right size bottom valve

11) Not enough immersion depth of bottom valve and inlet tube

Eliminating measures: Ask manufacturers about the correct immersion depth and use baffle to eliminate eddy.

12) Interval between impellers is too large

Eliminating measures: Check if interval is right

13) Damage of impeller

Eliminating measures: Check impeller and change the broken ones

14) The diameter of impeller is too small

Eliminating measures: Ask manufacturers about the correct diameter of impeller.

15) The wrong place of pressure gage

Eliminating measures: Check the direction and outlet nozzle or pipeline.

2. Fire pump will stop when operating for a while

1) Too high suction

Eliminating measures: Check the present net pressure head

2) Impeller and pipeline get blocked


Eliminating measures: Check if there is any barrier.

3) Producing air or the source line is leaking

Eliminating measures: Check if source line has cavitations or air leak

4) Air get into pump case because padding in stuffing box or seal wear

Eliminating measures: Check padding and seal to make sure if they need to be changed, and check if lubrication is normal.

5) Insufficient suction head when pumping hot or volatile liquid

Eliminating measures: Enlarge suction head and consult manufacturers about it.

6) Not enough immersion depth of bottom valve and inlet tube

Eliminating measures: Ask manufacturers about the correct immersion depth and use baffle to eliminate eddy.

7) Liquid is heavier than predicted value

Eliminating measures: Check proportion and viscosity

8) There is no correct padding in stuffing box 

Eliminating measures: Check padding and padding again

9) The lubrication of bearing is wrong or damaged

Eliminating measures: Check and change it according to the requirement

Insufficient fluid

1) Pump hasn't infused water or it doesn't exhaust properly

Eliminating measures: Check if pump case and source line are full of water.

2) Too slow speed

Eliminating measures: Check wiring of electrical machinery to make sure whether voltage and steam pressure are normal or not.

3) Too high system head

Eliminating measures: Check system head( especially frictional loss)

4) Too high suction

Eliminating measures: Check the present net pressure head

5) Impeller and pipeline get blocked

Eliminating measures: Check if there is any barrier.

6) Wrong rotational direction

Eliminating measures: Check direction of rotation

7) Producing air or the source line is leaking

Eliminating measures: Check if source line has cavitations or air leak

8) Air get into pump case because padding in stuffing box or seal wear

Eliminating measures: Check padding and seal to make sure if they need to be changed, and check if lubrication is normal.

9) Insufficient suction head when pumping hot or volatile liquid

Eliminating measures: Enlarge suction head and consult manufacturers about it.

10) Bottom valve is too small

Eliminating measures: Install the right size bottom valve

11) Not enough immersion depth of bottom valve and inlet tube

Eliminating measures: Ask manufacturers about the correct immersion depth and use baffle to eliminate eddy.

12) Interval between impellers is too large

Eliminating measures: Check if interval is right

13) Damage of impeller

Eliminating measures: Check impeller and change the broken ones

14) The diameter of impeller is too small

Eliminating measures: Ask manufacturers about the correct diameter of impeller.

15) The wrong place of pressure gage

Eliminating measures: Check the direction and outlet nozzle or pipeline.