Shallow well Jet pump short cycling

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Thepred

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I have a jet pump for my dug well. I went down today because I heard my pump kick in a couple times in a minute. What I see is my pressure is at about 25psi. So I turned water on And pump kicks in for about 20 seconds building pressure to about 25 then shuts off. My pressure switch is set to 60psi. I popped the top on pressure switch and notice that contact is made but pump is off. It just kicks back in on its own after about 30sec but shuts off every 10sec. Shuts off when pressure reaches 60psi (that’s what high is set to)Weird thing is contacts never flip off. I drained the system and checked pressure tank, it is charged to 18psi (cut in is set to 20psi on switch) Is the cutting in and out a sign of a bad bladder? Only house I have not gotten off is the little tube from pump body to switch but I figured if that was clogged would the switch not stay closed and pump run continuous? Any help would be appreciated.
 

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Check the amps. Most likely the pump is drawing high amps and just tripping the overload in the motor. These overloads will automatically reset in a minute or so and try again to get to 60 so the switch will open and shut off the pump. The pump has cycled on and off too many times and is not in good shape. Yes the tank is probably waterlogged and has a bad diaphragm, as cycling on and off destroys the tank, check valve, pressure switch, and everything else, not just the pump. You might try a new start capacitor, but probably won't help. Eliminate the cycling and not only will the pump and everything last longer but you will have strong constant pressure in the house. Setting the pressure switch to operate at 20/60 instead of 40/60 makes for terrible pressure in the house and is a dead give away that someone was trying to reduce the cycling.

 
You will need an amp meter to clip around one of the hot wires at the pressure switch or breaker. The SFA or Service Factor Amps will be listed on the side of the motor.
 
What causes a high draw by the motor? I did notice sediment and grit in the pump when I took the suction line off.
 
High amp draw is usually not caused by sediment. It could mean low voltage but most likely that the motor is going bad. Low amps usually mean restriction from sediment or something else in the line.

Motor going bad is caused by rapid cycling.
 
Well pulled out the old meter today and realized it was only rated to 10A. My pump is 20A at 115V. Going to have to find a 20A meter. One thing I did notice is the pump is running on a 15A breaker. If it was running high would it not trip the breaker? This would lead me to think it maybe running low. The pump is a 3/4 Red Lion. Only a year old.
 
You will need a clip around amp meter to check the amp draw from one of the hot wires. A 3/4HP on 115V should only draw about 14 amps. The internal breaker will trip before the one in the breaker box. If the pressure switch is staying closed and the motor still shuts off it is usually the overload in the motor that trips. Low voltage would also cause high amps. Check volts and amps.
 
Looked up online and it says for this pump 9A at 115v. When I metered mine it was only 4.3. This is low according to Specs. I checked the voltage and it is bang on. What would cause low draw on the pump. If draw is low would this trip something internally in control box?
 
Low amps just means the motor is spinning but not moving any water. It could be a melted impeller and the pump cannot move water. It could be a suction leak and loosing prime. Low amps won't trip the overload until the pump gets really hot and locks down, which would then trip on high amps.
 
I put a meter on it and lines going from pressure switch to control box is 120v. When pump kicks in it drops to 118v. The part I am confused is when I meter the line out of capacitor it measures at 183v? Is this normal? Franklin Electric confirmed it is an overload trip.
 

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