This document provides troubleshooting information for issues that may occur with jet pumps. It lists potential causes of problems such as a pump not starting or running, overheating, or not shutting off. For each cause, it describes how to check for the issue and how to correct it. Some common causes included low line voltage, defective motors or switches, leaks, and improper ventilation. The guidelines aim to help identify and resolve jet pump failures in an efficient manner.

1. Total Six Sigma Function Deployment in the design and Manufacturing of Jet Pumps
Jet Pumps
Pump won't start or run
CAUSE OF TROUBLE HOW TO CHECK HOW TO CORRECT
Blown fuse Check to see if the fuse is If blown, replace with a fuse of
OK proper size.
Low line voltage Use voltmeter to check Rewire any incorrect circuits and
pressure switch or tighten connections, replace
terminals nearest to the defective wires.
pump
Defective motor Check to see that Repair or take it to the motor
the switch is closed. service station
Defective pressure switch Check the switch setting. Adjust switch settings. Clean
Examine the switch contacts with an emery cloth if it's
contacts for dirt or dirty
excessive wear
Tubing to the pressure switch is Remove the tubing Clean or replace if it's plugged.
plugged and blow through it.
Impeller or seal Turn off the power, If the impeller won't turn, remove
then use a screwdriver to housing and locate the source of
try to turn the impeller or binding.
motor.
Defective start capacitor Use an ohmmeter to check Replace the capacitor or take the
resistance across a motor to the service station.
capacitor. The needle
should jump when contact
is made. No movement
means an open capacitor;
no resistance means the
capacitor is shorted
Motor shorted out If fuse blows when pump is Replace the motor
started (and the external
wiring is OK), the motor is
shorted.
B.Thamaraikannan(PhD)
9942755762 Sixsigma

2. Total Six Sigma Function Deployment in the design and Manufacturing of Jet Pumps
Motor overheats and overload trips out
CAUSE OF TROUBLE HOW TO CHECK HOW TO CORRECT
Incorrect line voltage Use a voltmeter to check at If voltage is under the
pressure switch or recommended minimum, check
terminals nearest pump. size of wiring from the main switch
on property. If it is OK then contact
the power company.
Motor is wired incorrectly Check the motor wiring Reconnect for proper voltage as
diagram per the wiring diagram.
Prolonged low pressure delivery Continuous operation at Install the globe valve on the
very low pressure places discharge line and throttle it to
heavy overload on pump. reduce flow and to increase the
This can cause overload pressure.
protection to trip.
Inadequate ventilation Check the air temperature Provide adequate ventilation or
where the pump is located. move the pump
If over 100 degrees F,
overload may be tripped on
external heat.
Pump Cycles Excessively (Starts & Stops Too Often)Pump starts and stops too often
CAUSE OF TROUBLE HOW TO CHECK HOW TO CORRECT
Leak in pressure tank For discharge or bladder
captive air tanks, drain the
tank and check the pre-
charge pressure. It should
be equal to or 2 psig below Replace the tank.
pump cut-in pressure. If
it's lower check welds,
braze joints, mechanical
joints and valve core with a
soap solution. If it's
defective, replace. DO NOT
ATTEMPT TO REPAIR BY
WELDING.
Defective air volume control This will lead to a Clean or replace the defective
water-logged tank. Make control.
sure the control is
operating properly. If not,
remove and examine for
plugging.
B.Thamaraikannan(PhD)
9942755762 Sixsigma

3. Total Six Sigma Function Deployment in the design and Manufacturing of Jet Pumps
Faulty pressure switch Check the switch setting. Adjust the switch settings. Clean
Examine the switch the contacts with an emery cloth if
contacts for dirt or dirty.
excessive wear.
Leak on discharge side of system Make sure all of the Repair leaks as necessary.
fixtures in the plumbing
system are shut off. Then
check all of the units
(especially ball cocks) for
leaks. Listen for the noise
of water running.
Leak on the suction side of the On shallow well units install Make sure above ground
system the pressure gauge on connections are tight. Then repeat
suction side. On the deep the test. If necessary, pull the
well systems, attach a piping and repair the leak
pressure gauge to the
pump. Close the discharge
line valve. Then, using a
bicycle pump or air
compressor, apply about
30 psi air pressure to the
system. If the system will
not hold this pressure
when the compressor is
shut off, there is a leak on
the suction side.
Leak in foot valve Pull the piping and then Repair or replace the defective
examine foot valve. valve.
Pump won't shut off
CAUSE OF TROUBLE HOW TO CHECK HOW TO CORRECT
Wrong pressure switch setting or Lower the switch setting. If Adjust the switch to the proper
setting "drift" the pump shuts off, this setting.
was the trouble.
Defective pressure switch Arcing may have caused Replace the switch if it's defective.
the switch contacts to
"weld" together in closed
position. Examine the
points and other parts of
the switch for defects.
B.Thamaraikannan(PhD)
9942755762 Sixsigma

4. Total Six Sigma Function Deployment in the design and Manufacturing of Jet Pumps
Tubing of pressure switch plugged Remove tubing and blow Clean or replace tubing if it's
through it. plugged.
Loss of prime When no water is being Re-prime if necessary.
delivered, check the prime
of the pump and well
piping
Low well level Check the well depth If undersized, replace pump or
against the pump ejector.
performance table to make
sure the pump and the
ejector are properly sized.
Plugged ejector Remove the ejector Clean and reinstall if dirty
and inspect it.
Pump Operates But Delivers Little Or No Water
CAUSE OF TROUBLE HOW TO CHECK HOW TO CORRECT
Low line voltage causing reduce Use voltmeter to check at If voltage under recommended
motor speed pressure switch or minimum, check size of wiring from
terminals nearest pump main switch on property. If OK,
contact power company
System incompletely primed When no water is Fill pump completely with water
delivered, check prime of through priming opening and
pump and well piping reprime pump
Air lock in suction line Check horizontal piping Rearrange piping to eliminate air
between well and pump. If lock
it does not pitch upward
from well to pump, an air
lock may form
Undersized piping If system delivery is Replace undersized piping or install
low, the piping and/or pump with higher capacity
plumbing lines may be
undersized. Refigure
friction loss
Leak in air volume control or tubing Disconnect air volume plug hole. If capacity increases, a
(Galvanized tank installations) control tubing at pump and leak exists in the tubing of control
plug hole. If capacity Tighten all fittings and
increases, a leak exists in replace control if necessary
the tubing of control
Pressure regulating valve stuck or Check valve setting. Inspect Reset, clean or replace valve as
incorrectly set (deep well only) valve for defects needed
B.Thamaraikannan(PhD)
9942755762 Sixsigma

5. Total Six Sigma Function Deployment in the design and Manufacturing of Jet Pumps
Leak on suction side of system On shallow well units, Make sure above ground
install pressure gauge on connections are tight. Then repeat
suction side. On deep well test. If necessary, pull piping and
systems, attach a pressure repair leak
gauge to the pump. Close
the discharge line valve.
Then, using a bicycle pump
or air compressor, apply
about 30 PSI pressure to
the system. If the system
will not hold this pressure
when the compressor is
shut off, there is a leak on
the suction side
Low well level Check well depth If undersized, replace pump or
against pump performance ejector
table to make sure pump
and ejector are properly
sized
Wrong pump/ejector combination Check pump and ejector Replace ejector if wrong model is
models against being used
manufacturer’s
performance tables
Low well capacity Shut off pump and allow If well is “weak”, lower ejector
well to recover. Restart (deep well), use a tail pipe (deep
pump and note whether well) or switch from shallow well to
delivery drops after deep well equipment
continuous operation
Plugged ejector Remove ejector and Clean and reinstall if dirty
inspect
Defective or plugged check valve or Pull valve and inspect. Clean, repair or replace as needed
foot valve and/or strainer Partial clogging will reduce
delivery. Complete clogging
will result in no water flow.
A defective valve may
cause pump to lose prime,
resulting in no delivery
Worn or defective pump parts or Low delivery may result Replace worn parts or entire pump.
plugged impeller from wear on impeller or Clean parts if required
other pump parts.
Disassemble and inspect
B.Thamaraikannan(PhD)
9942755762 Sixsigma