300 foot well pump

Users who are viewing this thread

Michael Young

In the Trades
Messages
508
Reaction score
101
Points
28
Location
North Carolina
Took a call for a well pump. Homeowner says the problem started about a month ago.

They have a 6GPM pump installed in a 300 foot well with a 30-gallon pressure tank. The well house and pressure equipment is 200-feet from the house.

Somebody else has already been out there to troubleshoot. They installed a new pressure tank, new pressure switch. everything up top is new. When we ohm out the pump wires, there is nothing suggesting the pump is bad. The pump kicks on at 40 and stops at 60. My gut tells me there is a volume issue. But their 30 gallon pressure tank provided adequate volume until about a month ago. So wtf gives?

Our tech suggested maybe there is some wear and tear on the impeller and the pump isn't moving enough water to keep up with demand. Don't want to pull a pump from 300-ft. if I don't have to.

What says our well geniuses? New pump? Bigger pressure tank? Something else.
 

Skoronesa

Member
Messages
35
Reaction score
21
Points
8
Location
East Bumfuk, Mississippi
I agree, pump is worn out. Do they get a lot of sediment? Have you measured the running current draw and voltage? Might be running slow if there's a poor electrical connection topside somewhere, high amp draw/low voltage might indicate that.
 

Reach4

Well-Known Member
Messages
38,798
Reaction score
4,412
Points
113
Location
IL
What is the symptom? Pressure tank used to fill in 60 seconds, and now takes 120 seconds, won't keep up with a shower, what?

Measuring the current can give some clue, but the water dropping lower, there being some restriction, or the pump impellers are worn would each reduce the current.

Higher than normal current could be a hole in the drop pipe.
 

Valveman

Cary Austin
Staff member
Messages
14,599
Reaction score
1,296
Points
113
Location
Lubbock, Texas
Website
cyclestopvalves.com
The pump is probably OK or it wouldn't reach 60 and shut off. As has been said, check the amps. A 1/2HP will pull 5 amps and a 3/4HP will draw 7 amps until the well is pumped dry. Then the amps will quickly drop from 5 or 7 to 3 or 5, and you know the pump has run out of water. A 30 gallon pressure tank only holds 7-8 gallons of water. The tank was never where the water came from. The well is not producing as much as it did in the past, the tank has nothing to do with anything but how often the pump cycles on and off. If the well does not produce enough for the house anymore the well needs to be worked on or you can use a cistern storage tank and make a weak well produce enough for several houses.

LOW YIELD WELL_and storage with two PK1A one pipe.jpg

Or dedicate the well pump strictly to the cistern like this.

LOW YIELD WELL_ CENTRIFUGAL_PK1A.jpg
 

LLigetfa

DIYer, not in the trades
Messages
7,497
Reaction score
575
Points
113
Location
NW Ontario, Canada
The pump is probably OK or it wouldn't reach 60 and shut off.
Is it possible for the volutes or intake to get clogged up with iron and reduce the volume yet still be able to reach cutoff? Same with worn volutes, would it not just take longer to reach shut off? I mean until it is so bad as to not shut off, it would still shut off.

If the system has multiple check valves, it could hide a leak that manifests as less volume at least as long as the pump can keep up. Only once the leak gets to be too large will it not reach shut off. Amp readings might point to a leak.

The pump curve can be plotted by measuring how many GPM you can draw into a bucket at different pressures.
 

Valveman

Cary Austin
Staff member
Messages
14,599
Reaction score
1,296
Points
113
Location
Lubbock, Texas
Website
cyclestopvalves.com
You gave all of the details EXCEPT what the problem is.
What is it not doing that it should be doing?
I don't know what the problem is until the amps are checked as mentioned. Starting out at full amps then dropping to half is pumping the well dry. Starting out at low amps could be worn pump or clogged intake as described.
 

PlumbNuts

SC Licensed Plumbing Contractor
Messages
251
Reaction score
83
Points
28
Location
Fort Mill,SC
Website
riverviewplumbingrepair.com
I don't know what the problem is until the amps are checked as mentioned. Starting out at full amps then dropping to half is pumping the well dry. Starting out at low amps could be worn pump or clogged intake as described.
Problem, Symptoms, what was the reason for the service call? Are they not getting any water? Are they just getting a trickle of water? Are they getting water really good for 5 minutes and then nothing?
He did not state what the "problem" was; just everything that had been done.
 

Michael Young

In the Trades
Messages
508
Reaction score
101
Points
28
Location
North Carolina
Problem, Symptoms, what was the reason for the service call? Are they not getting any water? Are they just getting a trickle of water? Are they getting water really good for 5 minutes and then nothing?
He did not state what the "problem" was; just everything that had been done.


the problem reported was that they can only run one fixture at a time. So they have water. Just shit volume. But they are using the same 30-gallon tank they've used all along.
 

PlumbNuts

SC Licensed Plumbing Contractor
Messages
251
Reaction score
83
Points
28
Location
Fort Mill,SC
Website
riverviewplumbingrepair.com
the problem reported was that they can only run one fixture at a time. So they have water. Just shit volume. But they are using the same 30-gallon tank they've used all along.
I do not want to insult you but I have to cover the basics first; Did you check the sediment filter?
 

Michael Young

In the Trades
Messages
508
Reaction score
101
Points
28
Location
North Carolina
The pump is probably OK or it wouldn't reach 60 and shut off. As has been said, check the amps. A 1/2HP will pull 5 amps and a 3/4HP will draw 7 amps until the well is pumped dry. Then the amps will quickly drop from 5 or 7 to 3 or 5, and you know the pump has run out of water. A 30 gallon pressure tank only holds 7-8 gallons of water. The tank was never where the water came from. The well is not producing as much as it did in the past, the tank has nothing to do with anything but how often the pump cycles on and off. If the well does not produce enough for the house anymore the well needs to be worked on or you can use a cistern storage tank and make a weak well produce enough for several houses.

View attachment 70910
Or dedicate the well pump strictly to the cistern like this.

View attachment 70911


Thanks man. Awesome. You just taught an old-timer seasoned plumber a few new things I didn't know. so big thumbs up!
 

LLigetfa

DIYer, not in the trades
Messages
7,497
Reaction score
575
Points
113
Location
NW Ontario, Canada
If the volume is good while the tank is drawing down and then goes to crap, the volume experienced would be what comes from the pump. The tank is not designed to be a source of volume. It is essentially a timer to control pump cycle times.

The tank however can provide clues, such as good volume during drawdown versus little difference during drawdown. Keep in mind however that pressure affects volume so during drawdown, the pressure starts high. I my prior post, In explained how to plot the volume curve of the pump.
 

PlumbNuts

SC Licensed Plumbing Contractor
Messages
251
Reaction score
83
Points
28
Location
Fort Mill,SC
Website
riverviewplumbingrepair.com
I honestly don't know. I wasn't the tech working out there. Louis is a solid tech. I'm going to assume he did. But I don't know for sure.
I just recently had the same situation except I relied on what the homeowner told me; I spent hours trying to determine cause until I said to the homeowner: "I know you told me that you changed the filter last week but I am going to check it anyway". If I had listened to myself instead of the homeowner I would have cheched the filter first.
I am pretty decent with wells but sometimes I forget the basics.

On another one I had changed the filter 3 days earlier and the problem popped back up, went out and had to change the filter again. Did this 5 times before sediment cleared up. (Well wall sheared off)
 

WY_WaterWellGuy

New Member
Messages
11
Reaction score
4
Points
3
Location
Wyoming
A lot of good info in this thread. To sum it up:

1) make sure there are no clogged filters in line to the house
2) with main valve to house closed, watch pressure gauge to make sure it stays constant — if pressure is dropping then there is a leak in the main line or in the drop pipe down the well. Depending on the severity of the leak(s) it could be contributing to a loss of volume supplied to the house. Obviously this test won’t work if there is a check valve by the tank and is only semi-conclusive depending on how many additional check valves there are down the well
3) watch amps while pump is running like Valveman described. Another common sign of a well going dry is an increased amount of sand/sediment being pumped from the well.
4) if all those things check out ok then I would pull the pump out of the pitiless and put a ball valve on it and check the flow rate at various pressures like LLigetfa said. Ideally you would have a sounder or some other similar device to monitor the water level in the well while you’re doing this so you could check your readings against the manufacturers pump curve.

Between all of these tests you will almost certainly discover something is awry with the well/pump. Good luck!
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks