drilled well issue

Hi,
Looking for some direction here. Want to get a couple of opinions, not just our local guy's.

I have a drilled well with these specs: (given at time of drilling in 2000, before I was owner of home)

depth: 257ft
water depth: 127ft
pump placement: 160ft
pump HP: 3/4, 220 v (3 wire)
water pipe diam: 3/4" (but I think this is wrong as it has a 1" T at the top of the well casing)
drilled with 8 1/2 drill bit, 4" casing


Ok, so the well is used primarily for irrigation. Historically the well has performed as expected without any lack of water. I have noticed that something wasn't right for probably a year, but due to low use it sufficed and I did nothing. There was one point where it had no pressure and it was determined that the pressure tank was bad so I replaced that (bought Oct. 2013, 20gal, 100-75psi). It seemed to have good pressure for a while and then it would loose pressure, but at times would pick back up. We are now going to use it more and need it to work correctly.

I just replaced the old pressure gauge because the needle wasn't moving smoothly. Current cut out is 58 psi, cut in is 44 psi, pressure tank is 42 psi.

Here is what happens when you simply open the valve to an open ended water hose:

Start at 58 psi
Slowly drop to 44 psi
Pump kicks on and pressure immediately drops (on first trial it dropped to 30 and then quickly on down to 15psi; on second trial it went directly to 15 psi)
Runs at 15psi with 5 gal/min rate (first trial ran for about 5 min, second trial 2 min)
Drops to 0 psi with 2-2.25 gal/min rate. will run at this rate indefinitely, with intermittent occasions of jumping back up to 10-15 psi.
After you shut off the valve/hose, it will immediately jump in pressure, quickly return to around 45-50 psi and then slowly (takes about 5 min) climb back up to cut out pressure.

So, what do you think my issue is? Be glad to provide any additional info that is helpful.

Thanks in advance.

You need a clip around amp meter. If the pump is pulling 7 amps, you have a hole in the drop pipe. If the pump starts at 7 amps and drops to 4, then you are either running out of water or a screen is clogged.

I guess you didn't like the answer I gave on my Forum:

It could be one of three things.
The water level could be down near the pump. Water levels do fluctuate during the year and more so during droughts etc.
The well could be a screened well and the screen is getting plugged up with mineral.
If you have a check valve up top, it could be holes in the droppipe, but I don't think it would make it to 50 plus psi if that were the case.

Do you know if the well has a screen or is it a rock well?

The reason for the rapid change in pressure is because of the tank. This is normal.

Click to expand...

speedbump said:

I guess you didn't like the answer I gave on my Forum:

Click to expand...

Yeah this has been asked on several forums. No matter how many times you ask the question, nobody is going to be able to wave a magic wand and fix the problem. We are going to need some more info to help you out.

Sorry guys. For some reason I have not been getting email notification of replies (maybe in Junk?).

I posted to several forum just trying to get a wide range of opinion and see how they all correlated. All the initial posts were done within 10 min of each other - not after getting replies.

I'll work on getting the "info" (amp results I presume) and post them once done... I'll have to get a clip around meter (mine is just a regular multi-meter with two leads).

I have no idea if it has a screen or is a "rock well". I gave all the information about it I have in the original post.

Thanks again.

You need a clip around amp meter. If the pump is pulling 7 amps, you have a hole in the drop pipe. If the pump starts at 7 amps and drops to 4, then you are either running out of water or a screen is clogged.

Click to expand...

There are not many other opinions if the above is happening.

Hi Guys. Finally got my amp-meter.

So, I clipped the meter around the power line going down into the well just before it dove through the well top (so that means it was between the pressure switch and the pump).

No matter when in the cycle (as described above) it was measuring the amps were always hovering between 11-13.

So what's that mean?

Also, not sure if this is pertinent, but the water is very heavy in iron... but my research has found that most of it is in solution and comes out either in the pressure tank or on whatever the spray hits.

Thanks.

Anything over 7 amps is too much for a 3/4 HP. Iron will build up in the impellers of a pump. That would be my guess. The iron is clogging the impellers, which makes the amps high and the water volume low. But at 11-13 amps, it should be tripping the thermal overload in the motor.

I agree, pulling that high of amps shouldn't let the motor run for more than a minute or so. Are you sure it's a 3/4hp and not a 1.5 hp?

no, I'm not really sure about anything regarding this pump. I was not the owner of the property when the well was drilled and the pump installed. All I have is a sheet of paper with some hand written information (given above) by the previous owner.

So does this mean that the pump needs to be pulled and inspected?

Also, (another thing I don't know much about) this is the meter I am using: https://www.amazon.com/gp/product/B005FSSKJA/?tag=skimlinks_replacement-20

I have it set on 20A and then I just open the clip and put it around the electrical wire going to the pump and the numbers show on the display.

I assume I'm doing that correctly.

Also, if I clamp it around the wire before/going to the pressure switch the amps seems to be a little higher like 14-15.???

From reading your initial post again, your well is only capable of around 2.5 gpm. This could be a plugged screen or the well just don't do any better for some reason.

If it runs continuously for minutes at a time, either the amp reading is wrong or your motor is bigger than a 3/4hp. Generally pulling almost double the nameplate amperage will trip a motor in less than a minute.

You are probably going to have to pull the pump to see what is going on.

it will run continuously all night long... just with low flow. Not sure about what you mean of it only being "capable of 2.5 gal/min", I watched it fill a 5 gal bucket in about a minute... maybe it is drawing down the water column above the pump and then 2.5 is as fast as the well can refill?? If that's the case, seems like it just needs to be put further down the well.??

So if it is a "clog" (screen, impeller, whatever) could it be a "clog" between the pump and pressure tank? I'm wondering specifically about the check valve and "T" piece there right by the tank.

Ultimately, I guess have to pull it, evaluate pump, measure current water level, etc...

Thanks

If the screen, tee, or check valve is clogged it should be pulling low amps. If the impellers are clogged it could be pulling high amps as it is. Either way 5 GPM flow is not very much for a 12 amp (probably 1.5HP) pump/motor.

ok, thanks. good to know.