well pump questions, jet vs submersable

[Dutch445]

Update,
During a phone call to the supplier for the pump and accessories,
I was told that if I went with 115v for the pump, that I need a 30 amp
circuit and breaker. I wasn't aware of this, and was told that I may
be able to get away with 25, but 20 would be not enough for a sumbersible.
(very reputable supplier)

I then went and looked at my electrical setup and found this:

There is a small sub box very near the existing pump setup, that isn't
being used for what it was intended when installed. There is a 50amp
double pole breaker in my main box feeding this box, with 2 large insulated
wires and a ground. (only feeds from 1 leg of breaker) there were a couple
basic 15/20 amp breakers in
the box and were really not being used for anything substantial.
I think this was from an old JenAir type stove. This is looking like a good
possibility for me to power the well , with at least a 25 amp breaker in this
box, and it's right above where the switch and tank are.

I also found an unused 230v wire terminating in the basement, that is only
being used to power the dishwasher now (110) and it is tied into
a 20 amp single pole breaker in the main box. I could easily return
this to a 230 circuit with a new breaker (2 pole) and end up about
10' away from where the pump is.

Neither of these circuits would be included in my transfer pump, so that idea
is going to have to go away. But, I am leaning towards going with the 230v
pump, and then using the extra 230v plug on my generator if I really needed
to power during an outage. (lead cord into the basement and maybe a small transfer box there)

so, if I have the ability to power with 230v, is there any reason to use
115v? other than that box is right there.

 

[TheGoose]

Hi Dutch. I used to be in the business, here are my $.02:

First off you need to make sure that your casing is at least 3". Anything less than 3" and you cannot use a submersible pump. Further, 4" casing is really ideal because the 3" casing takes a special pump, not the standard submersible pump, and it costs a bit more.

A submersilbe pump is superior to a jet pump in the following ways: it never loses prime, it never freezes, it is more efficient and quiet, and it cannot get infiltrated with bugs and the like since the motor is sealed. Jet pumps are inheritenely inefficient, lose prime, are loud, and bugs like to roost in the motor and plug up the vent holes.

I really can't answer your question on wiring. I always like to use 230V for the simple reason of your starting amperage. Whatever the pump pulls while it's running that number will be at least double while starting. That is why you need that 30 amp breaker for start-up. The 230V pump will pull ~6-7 amps while running but surge to 12-14 while starting. The 115V pump pulls 12-15 amps while running but surges to 24-30 amps while starting. Your generator will handle the 230V load better, you only have so many amps available.

As for the well being only 45' deep that may not be the case. What you need to do is pull out the pipe and have a well service co. test the well for it's production rate. To do this they use compressed air to jet the well with and that will tell exactly how much water the well is making. If it is not enough they may be able to treat the well to get the production up. That 1/2HP sub with a high water level (~20 ft) will make much more than 7 gpm. Every foot of 4" casing holds .6 gallons of water, so there is a little storage in the well, but you can still run out and may have to address that.

In my opinion the shallow jet pump is simply drawing the well down below it's pumping level (~25 feet at sea level, maybe 28 feet on a good day). You might be able to swap it out to a deep well set-up with a jet in the well itself and have much better pumping and reliability.

Good luck.

 

[Dutch445]

Thanks Goose,

it is a 6" well casing, pretty standard around here, and it already
has the pitless adapter. I have dropped a weight down the well about 45'
down, and realize that the single drop jet can only draw water down to
approx 25'. It happens a couple times a week, where we use enough water
that the pump will run for a long time before getting back to
50 lbs to trip the pressure switch. (sometimes I shut off the
breaker to let the well recover a few mins) I just think it makes sense to
drop a new submersible, as I have a feeling this jet pump may
not last much longer. Summer is worse, and we try to be careful when
we do laundry etc, but there are 4 and sometimes 5 of us at the house most
of the time.

I'm talking myself into going 230v, and getting a lower gmp pump, it should
have an easy life.

 

[maybar]

Thanks Goose,

it is a 6" well casing, pretty standard around here, and it already
has the pitless adapter. I have dropped a weight down the well about 45'
down, and realize that the single drop jet can only draw water down to
approx 25'. It happens a couple times a week, where we use enough water
that the pump will run for a long time before getting back to
50 lbs to trip the pressure switch. (sometimes I shut off the
breaker to let the well recover a few mins) I just think it makes sense to
drop a new submersible, as I have a feeling this jet pump may
not last much longer. Summer is worse, and we try to be careful when
we do laundry etc, but there are 4 and sometimes 5 of us at the house most
of the time.

I'm talking myself into going 230v, and getting a lower gmp pump, it should
have an easy life.

------------------------------------------------------------------
I would go with the voltage that makes your hook ups and disconnects the easiest for you.

I have two 45 ft. wells. One pump is 120V half horse that was here when I bought the ranch and the other is 240V half horse that was installed in a well I had drilled. There isn't one bit of difference that I can detect in the capabilities of the two pumps. Either pump will pump about 5 gal./ min at the well head.

One advantage of the 120V is it can be plugged in to any of the many 120V outlets available with a 20 amp. breaker.

 

[_RaT_]

In a situation like yours, there will be little problem going with a 120V configuration. The problem with 120 volt is when you have high current draw on a given wire size with a long distance of wire you get a voltage drop. Some things don't care about voltage drop, ie., incandescent light bulbs, resistance heaters to name but two. Motors are not fond of it, it will shorten their life and will increase the current flow through them making them hotter operating. That is why for high current, long runs, 240V is desireable and frequently used. It also allows for wire size that is smaller and thus less costly. In your case, you will be fine with 120V.

took a look at the pump tonight,
it's a gould, and it's dual voltage.
currently wired into 115, the label
says it's draw is 8.6 amps, with a
max load of 10.8
obviously the 230v ratings are 1/2
the 115.

i'll have to investigate sub pumps more,
i'm leaning towards a good 115v,
1/2hp, 7gpm.......

 

[Dutch445]

------------------------------------------------------------------

One advantage of the 120V is it can be plugged in to any of the many 120V outlets available with a 20 amp. breaker.

That's the confusing part, my supplier said 30 amp circuit, maybe 25, but no to 20 amp. ( I already have that right there, and can conver to 30 if needed) that was for the 115 pump, but all the specs I see for pumps never come close to 20 amps, unless they don't list the highest draw on startup.

last nite i was convinced to go 240, and if an outage occurs, use the
extra 240 outlet on the generator that's not powering the rest of the
transfer switch........

 

[maybar]

That's the confusing part, my supplier said 30 amp circuit, maybe 25, but no to 20 amp. ( I already have that right there, and can conver to 30 if needed) that was for the 115 pump, but all the specs I see for pumps never come close to 20 amps, unless they don't list the highest draw on startup.

last nite i was convinced to go 240, and if an outage occurs, use the
extra 240 outlet on the generator that's not powering the rest of the
transfer switch........

------------------------------------------------------------------------
Your supplier may just be covering his arse. Unless the wiring is a real long I don't see a problem with 120V. Sure 240 is better for longer wire.

I have 1/2 horse motors starting and running on 120V with a 20 amp breakers and in fact I have a 2 cylinder Emglo compressor with a 1-1/2 hp motor running on a 20 amp breaker.

So I still believe what's most convenient for you is the answer.

 

[TheGoose]

Strongly advise you to go 230V.

 

[_RaT_]

Its easy enough to test. Start up current lasts for but a fraction of a second to at most about a second. Even a 20 amp breaker is designed to withstand considerable current draw for that brief period of time. Some of the old breakers like Zinsco are not as good at this. Realize that even a light bulb draws an incredible amount of current until the filament heats up (which is really, really fast) and full resistance is realized. The filament after all, when tested by a ohm meter is basically a dead short. Air conditioner compressors are a good example of large start up current with relatively low running current. You are allowed to undersize the wire on a AC compressor with regards to the start up current or put another way, you can way oversize the breaker compared to the wire size. I disagree with Gooses comment. 240V while advantageous in many situations would appear based on what you have to be far less of a benefit than if you had a long run from the main panel with small wire. Having a large sub panel there with large feed wire (if I understand you correctly) is a huge bonus. Your voltage drop is pretty much a non issue. That is your main concern period.

That's the confusing part, my supplier said 30 amp circuit, maybe 25, but no to 20 amp. ( I already have that right there, and can conver to 30 if needed) that was for the 115 pump, but all the specs I see for pumps never come close to 20 amps, unless they don't list the highest draw on startup.

last nite i was convinced to go 240, and if an outage occurs, use the
extra 240 outlet on the generator that's not powering the rest of the
transfer switch........

 

[TheGoose]

If you HAVE to use 110V then do it.

All other applications I prefer 230V. I am a licensed water well pump installer in the state of Texas, I have been repairing pumps and wells for almost 20 years. 230V gets your current down. I can't explain it but 110V pumps don't have nearly as long of a life as their 230V cousins. I think they just have to work a smidgen harder because they lose more voltage then their 230V cousins.

No matter what, your watts will always be the same. W = V x A. Volts times Amps. You always want the fewest amps, it just makes it easier on the wire, motor, etc. Starting power is at least double amps, even if for a milisecond or two.

Also, I would try to stay away from the 1/2 HP. Go with a 3/4HP if you can. I never had good life out of the 1/2 HP motors relatively speaking. Don't know why either.

110V will work, but in my humble opinion they do not have as long of a life-span as the same 230V motor. Other than that it shouldn't be an issue.