Well water pump...comes on for no reason...anyone know why?

[BLeagues]

I am wondering if anyone can help me understand why my the water pump for my well would come on for no apparent reason and run for about 15 seconds or so and then shut off.

It comes on even if no one has turned a tap on, flushed the toilet or used the garden hose.

If anyone could help me understand this...it would be greatly appreciated.

Thanks

[dally]

If it's a submersable pump there is a leak between the pump and the pressure tank. The pressure is dropping off and repressurizing the tank. Or it's a faulty pressure switch.

[icedragon]

If pump is in your house (not in your well):

Your pump has a box (electrical) on it. Inside that box is a set of contacts. When the pressure in your system drops to a certain point the pump comes on until the pressure builds up to a certain point. Mine is set at 20 psi to 50 psi. Meaning the pump turns on at 20 psi and shuts off at 50 psi.
Yours might not be set the same as mine. Probally 20 - 40
Something is making those points close and start your pump. If you had no problems until now, your points may need to be replaced or ajusted, There is a little hose that runs from the pump to that electrical box, That may be froze or plugged, You may have a small leak somewhere between your foot valve and any tap in your house, Your footvalve may also be leaking.
That electrical box itself may also need to be replaced.
First thing, When the pump comes on look at your pressure gauge, see where it is when the pump comes on and where it is when the pump shuts off then post the results here.

You may also have air in the line and it's messing up that electrical box. The air pocket is passing by that little line from the pump to the electrical box giving a reading that the psi is 20 or below, forcing the pump to come on. When it does, the air pocket moves and the electrical box realizes the pounds are at 40 and the pump shuts off.

So, what to do. Have some primer water ready. I usually half fill my bathtub. Shut the power off to the pump. (110 volt should have a lightswitch, 220 will have a big gray box. Both are suppose to be above the pump) turn on a tap to take the pressure off the system, Take off the line that runs from the pump to the electrical box and blow in it to clear any blockage. Put a finger over one end and blow in it again to make sure it is not cracked. Install it back. Take off the priming nut (top of the pump) and pour some water in it until it is full. wait for a minute and watch the water level. It may go down a little while all the lines below the pump fill up. We never did anything to any of the pipes so it really shouldn't go down at all. If it keeps going down after you fill it a couple of times you have a leak somewhere. If the level stays normal, put the priming nut back on tightly and turn the power back on. The pump will take a minute to charge the system again. Post if you still have the problem.

[BLeagues]

Thanks icedragon...I will do as you say and let you know what the result is

[Chinna Dah]

My moms was doing that, she had a leak in one of her pipes.

[offroadwoody]

check the air pressure in your tank if its low your pump will come on for no reason at all and run for a short period of time also

[rebel2]

I agree with offroadwoody.Do you have an old galvanized tank or may be even some leaky taps.I have a galvanized tank and once a year i have to drain it down and i put about 19 pounds of air back into the tank.I usually know when its time to do it because the pump comes on just for a second every now again to bring the pressure back up.A good way to tell if it needs air is- when you turn tap on does the pump come on right away and when you turn tap off does the pump shut off almost right away.

[BLeagues]

This is what I have done so far.

There is a switch above my pump that controls the power to the pump. I have turned it off over night to see if it would come on first thing in the morning when I turned the switch back on.

It didn't come on right away after sitting over night with the switch off. So that leads me to beleive that I do not have a leak in the tank.

Icedragon...should I do as you say...or try some other route?

Thanks

[icedragon]

This is what I have done so far.

There is a switch above my pump that controls the power to the pump. I have turned it off over night to see if it would come on first thing in the morning when I turned the switch back on.

It didn't come on right away after sitting over night with the switch off. So that leads me to beleive that I do not have a leak in the tank.

Icedragon...should I do as you say...or try some other route?

Thanks

If you didn't lose any pressure then you have no leaks. Do what I suggested first. It sounds like air to me. After you try that post the results. If it works good if not I will have to see it. If you have an older tank, the ones with the air valve and bladder, You should have noticed air in the system if the bladder busted or is leaking. Easy to check if you bladder is still holding air. (if you have that kind if tank) On the front of the tank, there is a valve that looks like a tire valve. In fact that's exactly what it is. If you have a pressure gauge for checking the air in your car tires you can check the pressure in your tank. The pressure in your tank should be equal (+/- 5 lbs) to the pressure at which your pump shuts off. I can't give you an exact pounds it should be because people set them differently for different applications.
Becareful not to let any air out if you decide to check the bladder pressure.(again, if you have that kind of tank) If you ever need to put air in the bladder or if you want to up the pressure make sure you use a bike pump and not compressed air. Know how many pounds the bladder is rated for before you start putting air in it also.

[BLeagues]

Icedragon, I finally got around to checking the pressure that you asked for in your first reply.

The pump turns on at 25lbs and shuts off at 45lbs.

[BLeagues]

Further to my last post.

I have taken that hose off as you asked and have found no cracks and re-installed.

I checked the air pressure in my tank, it is 40 PSI.

The pump has yet to come back on for no reason, but it only usually came on in the middle of the night. So, I will wait and see what tonight brings and let you know what happens.

Thanks for all the tips.

[BLeagues]

The pump is still coming on.

It came on twice last night throughout the night.

So that is telling me that I have a leak somewhere. Nothing is dripping anywhere. However, I noticed that the toilet has a slight leak from the tank into the bowl. I am going to pick up a new flapper thingy for it sometime this week. I am hoping that this is the cause of the pump coming on through the night.

If not, this is going to be the death of me!

[BLeagues]

Alright, I fixed the toilet. Not leaking anymore.

yet the pump is still coming on...anyone have any suggestions?

[icedragon]

Icedragon, I finally got around to checking the pressure that you asked for in your first reply.

The pump turns on at 25lbs and shuts off at 45lbs.

Then you have a leak somewhere.

[icedragon]

Alright, I fixed the toilet. Not leaking anymore.

yet the pump is still coming on...anyone have any suggestions?

The leak could be anywhere from the footvalve to the point of use. If there are no leaks in your house then from the footvalve to your pump is leaking(assuming your pump is in your house)
Your going to have to inspect your line from your pump to your footvalve to find the leak. If it only coming on once a night, it's probally a leak in the line. If the foot valve would fail, the system would hold no water at all. However, the leak your looking for might still be underwater. Keep pressure on the system and inspect every inch of your line all the way to the footvalve. When you get to joints in the line, wiggle them to see if any water sprays out.

*****Before you do anything, half-fill your bathtub with water.*****

You should have a shut-off from your tank to the rest of the house. Shut this valve off tonight, Turn on all your taps to make sure there is no water flowing. See if the pump comes on. If it does, then your line to your well is leaking. If it doesn't then the leak is in your house.

By any chance did the line freeze over winter?

You can usually tell if the leak is not under water, when the pump turns on it will also suck air. When you turn on your taps you will sometimes get some air. Only coming on once during the night is not a bad leak. Might just be a clamp need to be retightened.

If you have hotwater heat(baseboard or in floor) these will have to be inspected too.

[BLeagues]

There are no visible leaks anywhere in the house. I have checked under all sinks...around the bathtub and the toilet.

I have electric heat.

The pump is in the house, but it does not appear to be leaking neither, nor does the tank appear to be leaking.

I was wondering about the box that has the hose going to it from pump. Where the contacts are that you mentioned earlier. What about it. I seen new ones at a local hardware store that are not overly expensive. Would that be a route to look at?

Thanks