Water is drawn in to a pump due to presence of atmospheric pressure. A pump can only pressurize a liquid while creating a low pressure at the inlet area. The liquid is pushed into the inlet area due to atmospheric pressure. The value of atmospheric pressure is equivalent to 33.5 feet of water column. Therefore the maximum depth a pump draw is 33.5 feet. However, due to existence of losses, vapour pressure etc., the depth a pump can safely draw water is limited to 25 feet.
Friction loss is force acting on the backward direction which opposes a smooth flow through a pipe. It is measured as an equivalent length of head and finally added to the total head. The value of friction loss increases with the flow rate, the roughness factor of the pipe and also with the viscosity of the liquid being pumped.
There is no such a rule. Some people add 1 foot to each 10 feet of pipe length. This may be good enough for a rough estimation. However the actual friction loss has to be calculated since it varies with the flow rate. The pipe friction values for various pipes and flow rates can be calculated using William Hazen formula.
Refer to the answer of A1
| Symptom | Cause | Remedy |
| Pump does not run | Power supply not available | Check power supply |
| Pump tripped from the overload switch | Reset overload switch | |
| Motor making a humming noise when switched on | Impeller/ rotor assembly stuck
|
Try to rotate the shaft from the fan end. If too tight get the services of a technician |
| Weak condenser | If you are confident, try to give a push start to the motor fan. If it runs it is a clear indication of weak condenser. Get the condenser replaced | |
| Starting winding defective | get the services of a technician | |
| Motor does not run at all | Motor winding burnt | Hand over to work shop |
| Motor runs but water not delivered
|
Leaking foot valve
|
Open the priming plug and pour some water. If the level stays start the pump. If the level drops replace foot valve |
| Leaking suction pipe | Get it repaired | |
| Leaking water seal | Get it repaired | |
| Water is pumped initially and stops pumping after some time | Water level exceeds suction limitations | Get an advice from the service /marketing team |
| Pump making an abnormal noise | Bearing failure | Change bearings |
| Comparatively taking a longer time to fill the tank than before | Foot valve blocked | Clean foot valve |
| Impeller blocked | Clean impeller | |
| Leaking water seal | get the services of a technician | |
| Loose connections in the suction pipes | get the services of a technician
|
