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  #1  
Old 09-21-2010, 10:05 PM
mikemc123 mikemc123 is offline
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Well Pump and control box issues

Hello,

I live on a small farm and have a well with a submersible pump.

From time to time, the water will stop running, so I go out to the well pit and do this:

Turn off the power to the control box/well pump.
Pull the cover (with the capacitor and other components mounted in it) off the control box
Put the cover back onto the control box
Turn the power back on

The pump will start running and pressure is restored, the pressure switch turns off the pump.

The control box indicates a 1/2 hp pump.

Now, sometimes I have noticed that the capacitor in the well pump looks like it may be leaking. Or, it seems like I need to go through this ritual several days or every time after some significant water use (like 30-50 gal or so to water the horses).

In this case, I replace the control box components (I buy a new box and slap the cover containing the components onto the mounted box) and this will hold me for a year, or maybe more.

In addition, I may adjust the air pressure in the bladder tank if it seems to be off (checking using a tire gauge).

I have also noted that this *tends* to take place at the beginning and end of summer, when things start to heat up, and start to cool down again.

So here is my question:

Why is it that the "control box cover ritual" works to get the pump going?
Is it normal that the control box should need to be replaced every year or so?
If the control box is not supposed to be replaced this often, is it indicative of something not quite right?

Thanks for any info
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  #2  
Old 09-21-2010, 10:38 PM
Crafter_Man Crafter_Man is online now
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Sounds like the connector terminals are getting corroded/tarnished/oxidized/whatever. It also sounds like moisture is causing or at least exacerbating the problem.

A few ideas:

- Seal the unit inside a box. But this will only work if there is a really good seal. Otherwise it's a waste of time.

- Install a small light bulb inside the box to increase the dew point inside the box.

- Apply some kind of anti-corrosion coating on the terminals.
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  #3  
Old 09-21-2010, 10:54 PM
johnpost johnpost is offline
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when you remove and reseat the box cover you reseat the contacts and also rub any corrosion off. makes good contact when there was poor contact.

if you see liquid or residue on the capacitor it is leaking and should be replaced.

a year is on the short end of lifetime for a capacitor. it does depend on your usage and your pump environment.

do not enclose any parts. it needs cooling, air and drainage. don't put a bulb inside the box, that is too much heat and uncontrolled, could be a fire hazard.

electrical anticorrosion paste on the contacts is a good idea.
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Old 09-22-2010, 12:00 AM
boytyperanma boytyperanma is offline
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Join Date: Dec 2005
Quote:
Originally Posted by mikemc123 View Post
Why is it that the "control box cover ritual" works to get the pump going?
That may or may not be what's actually doing it. Simply cutting the power could be allowing the thermal overload in the pump to reset. Also because the pump isn't pumping the well can recover so afterwords the pump has less lift to accommodate. What you do know is it works and you are buying yourself time.


Quote:
Is it normal that the control box should need to be replaced every year or so? If the control box is not supposed to be replaced this often, is it indicative of something not quite right?
No that's indicative of a problem. In general a control box will last half as long as the pump so most pumps go through 2 in a lifetime.

If your up for it and have an ohm meter and an amprobe you can do a few electrical tests.

With the power off. Take the control box apart. Identify a ground, if the pump is a newer installation it will have 4 wires running from the pump one of which is a green(ground) that's your best option.

Test ohms between ground and each of the 3 pump wires red, black, yellow. All should read 0. If you show any reading it means their is an insulation leak. A pump can survive for some time with an insulation leak but you are on borrowed time. This usually means there is a cut in the wire somewhere in the well but could also mean a problem with the pump itself.

With the power on put an amprobe on one of the power wires. Either one of the wires on the pressure switch or the black or yellow wire after the control box. When the pump turns on it will peak around 9 amps and should drop down to around 5. If it jumps much higher then 9 or that 5 is not very consistent or if overtime it draws more then you have an issue with the pump.


Overall my guess is you are due for a new pump. The control box being in the well pit is not an ideal environment and if possible it should be moved into the house. As the others noted the contacts in the control box could be the source of woes and simply ensuring good contact is a good first step.
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Old 09-22-2010, 09:42 AM
Crafter_Man Crafter_Man is online now
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Quote:
Originally Posted by johnpost View Post
don't put a bulb inside the box, that is too much heat and uncontrolled, could be a fire hazard.
A night-light bulb inside the box would not hurt anything.
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Old 09-22-2010, 04:26 PM
mikemc123 mikemc123 is offline
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[QUOTE=boytyperanma;12941972
If your up for it and have an ohm meter and an amprobe you can do a few electrical tests.

With the power off. Take the control box apart. Identify a ground, if the pump is a newer installation it will have 4 wires running from the pump one of which is a green(ground) that's your best option.

Test ohms between ground and each of the 3 pump wires red, black, yellow. All should read 0. If you show any reading it means their is an insulation leak. A pump can survive for some time with an insulation leak but you are on borrowed time. This usually means there is a cut in the wire somewhere in the well but could also mean a problem with the pump itself.

With the power on put an amprobe on one of the power wires. Either one of the wires on the pressure switch or the black or yellow wire after the control box. When the pump turns on it will peak around 9 amps and should drop down to around 5. If it jumps much higher then 9 or that 5 is not very consistent or if overtime it draws more then you have an issue with the pump.[/QUOTE]

Thanks for the detailed explanation, I'll give this a try. I've got a multimeter that I've checked the amp draw before and it looked ok, but not lately, and I've never checked the resistance.

Quote:
Overall my guess is you are due for a new pump. The control box being in the well pit is not an ideal environment and if possible it should be moved into the house.
This is what I thought at first, but I've been doing this for almost 5 years and it really does seem to be seasonal. I realize the well pit is not the best place, it can get humid in there (it is a cinderblock enclosure) but the well is several hundred yards from the house so that is where it was put.

Quote:
As the others noted the contacts in the control box could be the source of woes and simply ensuring good contact is a good first step.
Yes, the male contacts on the box cover look good, but it may be the slots in the mounted box, I'll clean these before I do the tests.

Thanks all for the replies!
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  #7  
Old 09-22-2010, 05:27 PM
boytyperanma boytyperanma is offline
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Quote:
Originally Posted by mikemc123
This is what I thought at first, but I've been doing this for almost 5 years and it really does seem to be seasonal.
I wouldn't count on the season having a direct causal effect. Many people make similar observations and in my experience it doesn't pan out that way. The pump is under a hundred feet of water it has no idea what's going on on the surface and the electronics to get the power there are very simple and it's unusual for them to be the ongoing reason for problems. Capacitors burning out like your seeing is more then likely a motor issue.

Quote:
I realize the well pit is not the best place, it can get humid in there (it is a cinderblock enclosure) but the well is several hundred yards from the house so that is where it was put.
When you say several hundred yards is that an actual number? I ask because at that distance you'd require #6 wire. That is substantial and wouldn't fit on your standard pressure switch and would be difficult to work with in a 1/2 hp control box. The problems you're having could be the motor is getting too much of a voltage loss with that distance.

If in the future you replace the pump and can't run a three wire between the house and the well to allow the control box to be in the house you could consider instead using a 2 wire pump, which would eliminate the need for a control box(starting capacitor is built into the pump) They are a little bit cheaper but have the disadvantage of not having a control box.


Quote:
Originally Posted by mikemc123 View Post
Yes, the male contacts on the box cover look good, but it may be the slots in the mounted box, I'll clean these before I do the tests.
If you are getting a new control box each time you should have plenty of backs around. Probably not worth the effort of changing the whole thing but the bridge(the plastic piece with all the females) pops out relatively easily. You could you can put one of the new ones in it's place. Just connect everything back the way you found it.
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  #8  
Old 09-24-2010, 10:58 AM
mikemc123 mikemc123 is offline
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Quote:
Originally Posted by boytyperanma View Post
If you are getting a new control box each time you should have plenty of backs around. Probably not worth the effort of changing the whole thing but the bridge(the plastic piece with all the females) pops out relatively easily. You could you can put one of the new ones in it's place. Just connect everything back the way you found it.
That's a good idea, if they seem tarnished enough then I'll use one of the newer bridges.

About the wiring, I should've explained, the power that runs the well pump comes in on a separate line altogether from that of the house. So there is the line from the power co, a meter, a breaker box, and then wiring runs right down into the well pit through conduit from the breaker box.
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