Urgent Well Pump Question

[Stringer]

Hey guys i have a 1.3 acre vacant lot im trying to build a home on. It came with a 2" above ground system that is junk and I'm having it abandoned. The well guy is coming tomorrow to put a new well in, a 4" submursible system with a 1HP motor. He plans to drill about 100 ft deep. This was just sprung on me moments ago. He is out of town and cannot be reached right now (figures)

Questions: Is a 1hp motor going to be enough for say, a 3 bathroom home and irrigation for many trees? The distance from well to proposed home is probably 200 feet or more. Any brands better than others? Basicly should I ask for a certain pump or just take whatever 1hp one he brings? I just don't know, and it's so permanent so I thought i'd get some opinions! Thanks!

 

[Travelover]

I'd ask the well driller for a recommendation for size after he determines how much water the well puts out. Mine was 23 gallons per minute and I went with a larger (I think 3/4 hp) motor on his recommendation.

Other considerations: I've never ended up using the full capacity and it requires a bigger generator to start it in a power outage.

 

[beppington]

1 HP is the standard here in N Central FL. Should provide great volume & pressure.

I have almost the exact same scenario (3BR house on 1 acre) & my 1 HP pump provide great volume & pressure, including a kick-butt irrigation system that does the whole acre (4 zones with 7 heads on each).

 

[Gator6x4]

Hey guys i have a 1.3 acre vacant lot im trying to build a home on. It came with a 2" above ground system that is junk and I'm having it abandoned. The well guy is coming tomorrow to put a new well in, a 4" submursible system with a 1HP motor. He plans to drill about 100 ft deep. This was just sprung on me moments ago. He is out of town and cannot be reached right now (figures)

Questions: Is a 1hp motor going to be enough for say, a 3 bathroom home and irrigation for many trees? The distance from well to proposed home is probably 200 feet or more. Any brands better than others? Basicly should I ask for a certain pump or just take whatever 1hp one he brings? I just don't know, and it's so permanent so I thought i'd get some opinions! Thanks!

A 1 HP motor will drive a 25 gallon per minute pump. The questions that you do not have answered at this time are: Well tank what size? How far is the water down in the well from the top, 20, 30, 40 feet? This will have a bearing on how many gallons per minutes the pump will actually produce. What size water supply line do you intend to use? A 1/2" supply line will greatly restrict water volume, whereas a 2" water supply line will provide plenty of volume. Water pressure will be the same in both, 1/2" and 2" but the water volume, gallons per minutes from the facuet will be greatly reduced if 1/2" line is used. What PSI do you have in mind for the system, 40, 50, 60? The tank and the pump have got to be sized together to prevent damage to the pump. Some of the new constant flow pumps allow for a small tank and maintain good pressure by running on demand. The list goes on and on. I would recommend doing a web search on well pumps and well tanks.

 

[Cat_Driver]

No one can answer that till the well is drilled. You need to know what is the well recovery rate, and only the driller can answer that.

A 8HP motor will is a waste of money if the well only produces 2 gallons a minute.

On the other hand if the well produces 100 gallons a minute then it's not that much more to go with a larger motor while the well is open.

From what well guys have told me it's better for a pump to run a longer time than a shorter time - don't know why just what I've been told, so smaller motor is better than larger motor.

 

[Kays Supply]

The undersize vs oversize issue has to do with pump short cycling. If you are going to use lots of water all the time bigger is better. If you aren't going to use it, it will cause it to run too short a time and that isn't good. There are systems, like Jaccuzi had, that will keep it running as long as there is demand, but it can cause pressure issues if it is too much over sized. Then you need regulators and controls. Some of the high end pumps have a sensor system that ramps the pump up as need. I have no experience with those.

 

[Stringer]

wow this is all great advice, thanks alot!

sounds like a 1hp is probably ideal, but i'll leave it to the installer and see what he finds tomorrow. interesting info about short cycling. Apparently it's the same as air conditioning units. Bigger is not better due to short cycling, or so i've read.

 

[bp fick]

Don't worry about it now. You can deal with these issues tomorrow.

You can always increase your storage capacity as compensation anyhow.

 

[JL Sargent]

These guys build some of the best well pumps! When dealing with water systems a little over kill is sooooo much better than a little under kill.:thumbsup:

GRUNDFOS

 

[mmurphy]

The question is head for GPM, not just HP.
Most city water systems with a 3/4" line coming in a house nets aprox 5 gpm through water meter base.
I would think if your well contractor has been in business long enough, feel comfort in to know he would probably have good knowledge in what he is doing.
If you have large amounts of water needed for short times, or other types of usage, bring concern up with him, for I am sure with economy as is, he would not want a unhappy customer.