Pumps FAQ: TROUBLE WITH YOUR SUBMERSIBLE PUMP FOR DUMMIES
RULE NUMBER 1 - EVERYTHING EVENTUALLY FAILS
RULE NUMBER 2 - USUALLY THE DAY AFTER THE WARRANTY RUNS OUT
RULE NUMBER 3- THE PERVERSE NATURE OF MACHINES REQUIRES THEM TO FAIL WHEN YOU ARE EXPECTING THE GREATEST NUMBER OF GUESTS.
BEFORE YOU EVEN READ THIS: GO OUT AND TURN THE PUMPS CIRCUIT BREAKERS OFF THEN ON AGAIN OR REPLACE THE FUSES WITH NEW ONES .IF IT RUNS, LISTEN FOR WATER RUNNING WHEN OR WHERE IT SHOULDN'T. GIVE YOUR PRESSURE GAGE A THUMP AND MAKE SURE IT WORKS, IF NOT REPLACE IT FIRST SO YOU CAN TELL WHAT IS GOING ON.
1. No water
A. Motor runs - you can hear it or feel the pipe vibrate or amp check if you have an amprobe.
a) Hole in drop pipe or coupling, bleeder valve blown out.
b) Massive leak in your system. Pump is delivering water just not where you want it to go.
c) Jammed or backward check valve. It happens.
d) Pump is out of the water
e) Pump inlet screen plugged. Very rare.
f) Pump worn out. Impellers worn. If it has pumped sand or is very old this is possible.
g) Pump shaft broken or coupling stripped. Very rare these days.
h) Pump air locked.
j) Water level has dropped so far pump can't lift to surface.
B. Motor doesn't run
a) No power to pump - this is the most common thing.
b) Motor failed
c) Wires down well broken or bad splice.
d) Control box problem, bad capacitor or relay or cover is not on.
e) Pressure switch problem - easy to fix but usually wishful thinking.
1) Look at the contacts. If they aren't closed figure out why.
The switch thinks the pressure is at shutoff level. Did it freeze last night?
Possibly bad pressure switch or plugged inlet.
2) Burned contacts don't mean much. Bugs in the contacts are a common problem. Clean them off with the eraser end of a wooden pencil. These contacts are always
f) Overload tripped. Look for a red button on or under control box.
g) Pump locked up.
h) Both wires to motor or control box are connected to the same leg in the panel .
2 . Not enough water, or pressure - motor runs, perhaps runs all the time
A. Leaks - surprisingly small leaks can lose a lot of water. Common problem.
a) Leaks in your house system.
Shut off line between tank and house and see if pump builds up pressure normally.
b) Down the well: Holes in drop pipe or bleeder valve.
B. Pump problems
a) Pump too small for demand
b) Pump impellers worn by sand
c) Water level has dropped below what pump is designed for
d) Check valve jammed either down well or on surface.
The nut can also come off the plunger and improper pipe fittings can prevent plunger travel.
e) Plugged inlet screen. Very rare.
f) No water in well or pump not set deep enough.
g) Motor coupling stripped or shaft broken. Sometimes can still pump.
C. Tank problems
a) Waterlogged tank will cause pump to go on and off continually.
This also results in apparent low pressure. This is very common.
b) Surface check valve stuck open allowing water to run back down the well or stuck closed preventing water from
D. Electrical problems
a) Improper connections at control box. If color codes were not kept the pump will attempt to start on the
run winding and will not be able to continue running
b) Low voltage. 230 volt pumps will run on 115 volts but not very well and will cut out and reset.
This happens when one pole of a two pole circuit breaker has tripped. Pull both poles all the way to off,
then back to on.
c) Motor has internal short which is not bad enough to make it stop totally but results in intermittent operation
or less than full speed operation. This is a frequent motor death mode.
3. Bad water
A. Milky -air or gas in water.
1) Natural entrained air or gas - not much you can do about it.
2) Tank air problem
a) Bad air volume control
b) Pumping water level too low allowing air to be sucked into pump
c) Excessive draw from tank allows air into house lines
B. Sandy - well problem, made worse by frequent starts, well driller problem
C. Tastes bad - try an activated carbon filter
D. Looks bad - particulates in water, try a cartridge filter
E. Stains sink -Iron and/or manganese in water, water treatment problem
F. Stinks - hydrogen sulfide gas or methane
G. Slime in strainers - iron bacteria, chlorinate well
4. Fuses blow, breakers trip, overloads trip
A. Happens immediately when power applied to motor
1) Short to ground in motor, cables or supply wires to pressure switch.
Remove control box cover or disconnect leads to motor to see where the problem is.
Shorts make things trip very fast.
2) Worn out breaker, wrong size breaker, non-time delay fuses can't take starting current.
3) Control box problem causing start winding in motor not to operate. Usually times several seconds to trip.
4) Low voltage
5) Pump locked up
B. Happens when motor has been running
1) Low voltage
2) Short cycling, too many starts
3) Control box too hot due to sun or other heat source.
4) Control box problem - bad capacitor, relay, or wrong size
5) Fuses or overloads too small.
6) Circuit breakers worn out - they will only trip so many times.
7) Frequent low head starting causing up thrust
8) Worn pump - usually causes low amps but can also cause high amps.
9) Pumping a lot of sand.
10) Wires too small or contacts somewhere very bad causing high voltage drop.
11) Well is so crooked the pump and moor have been forced into a bind. You have to work at it to create this one.
5.Pumps starts and stops too often. This is very hard on submersible pumps and motors.
A. Water logged tank.
1) Galvanized tank
a) No air charging system - drain tank and open a fitting to break vacuum.
This can always be used as a temporary fix on any tank.
b) Air leak in tank above water level
c) Surface check valve is leaking and preventing snifter valve from taking in air.
d) Snifter valve (usually screwed into check valve) is not working. It should suck in air every time
the pump stops. Frequent problem area.
e) Bleeder in well is not letting water leak out of the pipe so air can be sucked in by the snifter.
f) Pump runs constantly and so never cycles to put air in tank.
g) Air volume control letting too much air out.
2) Bladder tank
a) Bladder is ruptured. Tank will feel heavy and water will come out of tire core valve on top of tank. b) Tank has too little pre-charge air in it or, too much. It needs to be just right which is 2 pounds less than the start pressure of the pump, measured with the tank drained and the pump off.
B. Air logged tank - air volume control bad or too much air being pumped in.
C. Defective pressure switch or set wrong
D. Tank too small for pump size and demand.
E. Check valve on surface may be jammed or partially open
This is for people who are familiar with electricity and have a voltmeter, ammeter and
ohmmeter and enough common sense not to fry themselves.
There are two basic symptoms:
1) Motor does not run
2) Something trips out
1) Motor does not run
A) Makes no sounds - this most likely means no power to motor. First make sure you have put he cover back on the control box if it is 1 HP or less.
Start at the pressure switch with the switch wedged open with a non-conductor and measure voltage leg to leg-AND to ground.
If you do not have 230 volts (unless it is a rare 115 volt motor) trace back to
the circuit breaker or fuse box. If you have 115 volts to ground on both legs
at the pressure switch, you have both legs on the same hot leg and thus zero potential difference between them. Put one leg on the other hot leg.
If you have 115 volts to ground on one leg and zero on the other, one wire is broken or one half of the 230 volt breaker is defective or tripped.
If everything is zero at the pressure switch the wires are broken or the breaker is bad, or tripped, or the main power is out.
If everything checks out then there is an open in the motor or in the control box or the wiring to the motor. Start by disconnecting the power at the breaker then di sconnecting the wires that go down the well from the control box. Use an ohm meter to check for continuity between all three wires (or two if it is a two wire pump). Also check each leg to ground. All should be infinity or at least 10 megohms to ground. The resistances leg to leg are small. The yellow is common and the yellow red (start) should be more than
the black (run) to yellow. An open indicates a broken wire, bad splice or bad
motor. A low resistance to ground indicates a bad motor or sub cables that are damaged.
B) Motor hums, buzzes . This is either low voltage, a bad control box, mixed wire color code , shorted motor.
Do all the checks listed in ( A) above. If it is not covered in (A):
1) If the pump is new
a) Ohm check the wires from the motor. The highest amp reading will be Red to Black. The next highest Yellow to Red and the lowest Yellow to Black. If your readings don’t agree, the color code is mixed down below.
2) Wrong voltage control box. Only possible on ½ HP pumps where 230 volt or 115 volt motors are made. If 115 volt box is used on a 230 system, the control box relay will be expecting much higher amps and so will not drop out the start winding.
3) Control box problems. Sometimes they are bad out of the box. 11/2 HP and above sometimes have incorrect connections. Rare but it happens.
There are four possible components in a control box:
Start capacitors- black cylinders- most likely to fail. Look for burned off connectors, black gunk oozing out. If it looks OK, you need an analog ohm meter. Short across the capacitor to discharge it, then put the ohm meter on it. It should show a low reading which increases to infinity over several seconds as the capacitor charges. These are cheap and readily available at any electric motor shop.
Run capacitors - usually metal cylinders - almost never fail- almost. Overload relays - “Klixons” the red button. They fail. If they trip out, check the amp draw. If it is normal, the overload is bad. By-pass it with a jumper until you can get one. ( or forget about it)
Start relay- black or blue square . Most difficult to diagnose. It depends on whether they are solid state (blue, or on some original, a small semi- conductor looking thing) or electro-mechanical, a 2" square with MARS written on it somewhere. See Franklin-electric.com (www.fele.com) for details on this. If you get to this point, just replace the control box.
Control box problems are often caused by short-cycling of the pump.
2. Something trips out. This means the pump overload or a circuit breaker or fuse. This does not mean the pressure switch. First check for proper voltage starting at the circuit breaker, then the pressure switch, then the leads going down the well. This can be difficult with control boxes that have covers that pull the guts out with them. These are for your safety and the manufacturers safety from lawyers, but they are a pain to troubleshoot. People in the industry make jumpers from two old control boxes. Your best bet is to put a short jumper on the three pump leads and wire nut them where you can get a probe on them. This also lets you make amp readings and ohm readings.
A. Circuit breaker trip. If there are no voltage abnormalities, this is either a dead short somewhere or a bad breaker. If it takes some time to trip, look for bad breaker, too small a breaker or hot breaker box. It may also be a small ground fault resulting in high amps but usually the pump overload will trip first.
If you are looking for a short or ground fault, open the circuit breaker so you don’t blow up your ohm meter, then start at the pump, disconnect the leads going down the well and check each leg to ground. You should get near infinity. Next check the yellow to red and yellow to black. These reading should be very low, 2 to 12 Ohms. The yellow to red should be higher than the yellow to black. The exact readings are available from the Franklin-electric.com web site, but they aren’t that critical. If you don’t find anything down the well, start working your way back to the pressure switch, then to the breaker, until something shows up. Fix it. This will probably require pulling the pump or digging. The good news is that you will get your exercise without paying health club dues.
B. Overload trip. This means high amps or bad overload. Again, assuming nothing showed up on the voltage check, take amp readings on all three wires. Look up the service factor amps on Franklin-electric.com, and compare. These motors are actually designed for the service factor, i.e. a 2 HP motor is actually a 2.3 HP motor, so it doesn’t hurt them to run at SFA. If the amps are uniformly high by 10 to 15% it probably means the motor and/or pump end are shot. If one leg is high it indicates a ground fault. The red leg is the start winding, the black is the run winding and the yellow is common. Any electrons that go down the red and black have to come up the yellow or go to ground. A single high leg is probably a ground fault. If you put your amprobe around all three legs at once and have any current show, it is a ground fault. It can be motor or sub cable.
When the motor starts you should see a momentary blip on the red lead amps which may fall off to zero on small pumps, or fall to a low level on capacitor start/capacitor run control boxes. If you don’t see this, look for control box problems or an open in the start circuit. This usually is accompanied by high amps on the black-yellow leads as the pump tries to start. It is possible for the pump to start sometimes without the start circuit.