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120v or 12v pump for lake draw/pressure tank setup?

fisherman

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Joined
May 3, 2022
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Location
NW Ontario Canada
Good Morning,

I need a water pump and pressure tank for my small cabin. My water source would be coming from the lake. Pump house is about 80ft from the lake and 15ft higher than the intake. Water use would be mostly for drinking, showering and dishes so not a ton of daily usage.

I'm in the process of designing a 1500w 24v solar setup using 2x100ah batteries. I'll likely go with the Victron multiplus 24/2000/50 for the inverter to get 120 and could install a converter to drop the 24v down to 12v.

Currently considering a shallow well 1/2hp 120v pump to use off of the inverter or get a 12v pump. Either way I'd like to have a pressure tank so it's not cycling all the time.

Would my setup power a 120v pump at this hp? I wouldn't use the pump often but figure it might work better than the 12v with a pressure tank?

Please let me know your thoughts.

Thank you
 
It takes a lot of power with a Pressure tank as the pump has to fight the increasing pressure which translates into load.
Example: I have a 120V Grundfos Deep Well Soft-start pump, 50 Gallon pressure tank, with a 40PSI Cutin and 52PSI cutout. Being softstart (only way to go with solar, battery) it starts up at 500W and stages up to finish at 1200 watts. At 1200W it is pulling about 42A from my 24V system.

The 120V pump is the way to go and almost all can be bought with a Softstart module or can have their controller changed. Softstart eliminates the huge surge pull to start a motor.
 
Note the pump in this thread. My friend purchased one of these. We tested it with a 300w 60 cell panel (not battery) and it worked well. Even pumped (not the same volume) with the panel very "off angle". We tested it with a 24v battery as well. It would be worth a consideration.

Edit:
We didn't pump into a pressure tank but just through a garden hose.
 
It takes a lot of power with a Pressure tank as the pump has to fight the increasing pressure which translates into load.
Example: I have a 120V Grundfos Deep Well Soft-start pump, 50 Gallon pressure tank, with a 40PSI Cutin and 52PSI cutout. Being softstart (only way to go with solar, battery) it starts up at 500W and stages up to finish at 1200 watts. At 1200W it is pulling about 42A from my 24V system.

The 120V pump is the way to go and almost all can be bought with a Softstart module or can have their controller changed. Softstart eliminates the huge surge pull to start a motor.

Thanks for the info! In my case I would run a shallow jet pump and not a submersible. I wonder if soft-start is available for something like a Wayne or Goulds 1/2 shallow jet pump?
 
Thanks for the info! In my case I would run a shallow jet pump and not a submersible. I wonder if soft-start is available for something like a Wayne or Goulds 1/2 shallow jet pump?
Just to throw it out there, a submersible has 1 major advantage over a jet pump and that is that you never lose priming on a submersible unless you drain the lake.
 
water source would be coming from the lake. Water use would be mostly for drinking, showering and dishes so not a ton of daily usage.
anaerobic flagellated protoazoan parasites
process of designing a 1500w 24v solar
That suggested screw pump into a reservoir at the cabin would run only as you choose and a 12V RV pump with internal pressure buffer ($90) doesn’t require a pressure tank for steady 35-40psi

A shipping tank for food grade items is usually found $50-$150 used, and then you can bleach for your health. I have one on a 4x8 trailer for “harvesting” spring water.

At only 1500W i’d go 12V. Then you can use the plethora of inexpensive LED 12V lighting options etc. The 300W pump will run fine on that, and do many things from cell boosters to laptops are already 12VDC and RV items are readily available.
 
That suggested screw pump into a reservoir at the cabin would run only as you choose and a 12V RV pump with internal pressure buffer ($90) doesn’t require a pressure tank for steady 35-40psi

Would it keep a prime and pull water given the distance/height from the water?

A shipping tank for food grade items is usually found $50-$150 used, and then you can bleach for your health. I have one on a 4x8 trailer for “harvesting” spring water.

I have some of those but would prefer to go the pump/pressure tank route.

At only 1500W i’d go 12V. Then you can use the plethora of inexpensive LED 12V lighting options etc. The 300W pump will run fine on that, and do many things from cell boosters to laptops are already 12VDC and RV items are readily available.

The building is already wired for A/C so I'll probably build out a 24v system as I will add to it over time.
 
Would it keep a prime and pull water given the distance/height from the water?
The pump a prior poster suggested is a submersible/casing pump. So it can’t lose prime below water.
I have some of those but would prefer to go the pump/pressure tank route.
The tank/reservoir doesn’t pressurize. It holds your bulk lake water so you can accurately add bleach to disinfect from beaver fever and other protozoans, cysts, and bacteria every time you add 200gal of lake water. Giardia ain’t fun.

The 12V RV balanced pumps provide adequate pressure without pulsing and no need for a pressure tank: less to fail and less to buy.
The building is already wired for A/C so I'll probably build out a 24v system as I will add to it over time.
That small system won’t run an air conditioner anyway and you likely will never want it in Maine.
Do you anticipate other simultaneous AC loads to exceed 2000W cumulative? That’s over 16A 120VAC.

If at 12V, very low watt LED lighting can be used which reduces the AC draw from the inverter quite a bit. Plus they’re inexpensive and last for years and do not require an inverter. That way you don’t even need the inverter idle draw and can run it only when AC is required. 24V doesn’t add anything but higher amps at a given wire size and at 12V your lights, phone chargers, and other basics still will work even if the inverter dies.

If you are looking for a city-level of 120 AC and want to run an air fryer than 24- or 48-volt is probably in order. Under 2000W? Like for a fridge, coffeemaker, shopvac etc. then 12V is sufficient.

Do what makes sense to you. For a cabin or a camper I just like the simplicity, redundancy, reliability, and ease of procuring components of 12V. Here in Vermont it would take something major like a direct lightning hit to make me go down.
submersible has 1 major advantage over a jet pump and that is that you never lose priming on a submersible unless you drain the lake.
And I just reminded myself that’s a 24V pump :( Too bad
But 120V similar pumps aren’t badly priced, and in full sun this would fill the reservoir easily in an hour. Those small portable gasoline pumps would be 10-15 minutes but I’d use solar and a float switch myself.

Either way the tank lets you sanitize the water. Alternatively, you might dig an eight foot hole and get clean water. Not needing chlorine.

Out in nowhere, Maine I’d probably try to dig a well or use a 120V lake water pump into the reservoir.
 
Just to throw it out there, a submersible has 1 major advantage over a jet pump and that is that you never lose priming on a submersible unless you drain the lake.
from a safety perspective, I'm not sure I'd be permitted to put a submersible in the lake do to potential electrical hazard?
 
The tank/reservoir doesn’t pressurize. It holds your bulk lake water so you can accurately add bleach to disinfect from beaver fever and other protozoans, cysts, and bacteria every time you add 200gal of lake water. Giardia ain’t fun.

The 12V RV balanced pumps provide adequate pressure without pulsing and no need for a pressure tank: less to fail and less to buy.
I'm looking at a filtered UV light setup. My concern is I wouldn't be up there often so leaving a tank full of water that long might have it's own set of water issues.

Do you anticipate other simultaneous AC loads to exceed 2000W cumulative? That’s over 16A 120VAC.

Aside from the water pump draw, I don't think I'd be close to 2000w.
If you are looking for a city-level of 120 AC and want to run an air fryer than 24- or 48-volt is probably in order. Under 2000W? Like for a fridge, coffeemaker, shopvac etc. then 12V is sufficient.
I'm torn. I feel like I'm just on the verge of 24v making sense. I guess I want to future proof the system.

You're right though, I would benefit from some 12v items so maybe I look at a converter down to 12vdc.
 
Ontario: You can direct draw from a lake with an external pump. A submersible is not permitted in a lake. Alternately you can have a shallow Well that is setback from the lake to draw the water. But I have a fair idea of where you are and you are standing on Granite & Basalt which is just a few inched below your toes, that can be an issue too. (not digging that out by hand my friend), well, unless you are 22 yrs old, not too bright LOL.

BTW: 12V is terribly limited especially when converting to VAC, Stepdown Conditioned converters are cheap & pretty reliable (don't get no name "SumYungGuy" product through.

12V@250A = 3000W, 24V-6000W or 48V-12,000W

1200W Inverter Microwave pull 72A from 24V
Oster Percolator (with carafe no heating element) pulls 55A from 24V.
Just for you to consider it.

Finally, if building fresh now, build WITH future thinking, it IS expensive to upgrade after the fact. Build whatever system with a Solid Foundation that addresses future expansion/growth is the best $$ insurance you can give yourself. Everyone ALWAYS underestimate their usage by a minimum of 25% and sometimes worse and within 12 months they are grumbling, upgrading and not telling anyone because they are embarrassed for not engaging in Critical Thinking from the start.

Sorry to put it that Bluntly but I've been at this too long and seen far too many run around that same mulberry bush, over & over & over again, there's a frickin MOAT around that ruddy bush now.

BTW:
I went from "Value" 24V/3000W Inverter (1,000) to a Samlex EVO 4024 4000W Low Freq Inverter (2100)
Upgraded from the original Rolls Surette Heavy Lead $3500 of FLA (11 useable kWh) to 30kWh of LFP ($ I'd have to add it up)
Changing BMS to Normalize everything - dumping $2200 worth of BMS & Active Balancer for new combined JKBMS models for $1100.

Have a peek at : About My System (updated Dec-17-2020) which is sadly terribly out of date due to my present final rebuild being incomplete BUT it may provide you with a lot more handy info, look into the blue spoilers too.

Steve
 
I'm looking at a filtered UV light setup
That can have a significant amp penalty.
Aside from the water pump draw, I don't think I'd be close to 2000w
Why not build two systems? 12V lights, 24V-120VAC for ‘stuff?’
I’ve had blown fuses and other weird things (that disabled 120VAC but 12VDC has always given me dependable lights and charged my phone.
12V is terribly limited especially when converting to VAC, Stepdown Conditioned converters are cheap
I’ve never found 12V to be terrible or limited, and it’s easy to charge with car if necessary.
But I use US12V, not EU or hydroQuebec 12V so there’s that.
 
from a safety perspective, I'm not sure I'd be permitted to put a submersible in the lake do to potential electrical hazard?
Ontario: You can direct draw from a lake with an external pump. A submersible is not permitted in a lake.


So you can't submerge a submersible pump in a lake because of electrical hazards, but you can submerse it in a pipe full of water? That makes no sense, but then again that's normal with a lot of ruling bodies. o_O
 
So you can't submerge a submersible pump in a lake because of electrical hazards, but you can submerse it in a pipe full of water? That makes no sense, but then again that's normal with a lot of ruling bodies. o_O
NO because it can pull in sediment and critters. Talking about submersibles like a deep well pump or some of teh utility pumps. British Columbia has som REALLY weird ad peculiar rules oivey.
 
NO because it can pull in sediment and critters. Talking about submersibles like a deep well pump or some of teh utility pumps. British Columbia has som REALLY weird ad peculiar rules oivey.
Aaahhh... because there's no way critters would get sucked into a jet pump. Gotcha. :)
 
Who said anything about governments making smart choice or why they make whatever rules. There are lists of stupid laws & rules everywhere.
Fed/State/County/MInicipality/city - town - village "govern mentals" come up with krap for whatever reason.
 
So you can't submerge a submersible pump in a lake because of electrical hazards, but you can submerse it in a pipe full of water? That makes no sense, but then again that's normal with a lot of ruling bodies. o_O
No stating this from any knowledge of any rules.....Electricity conducted to water must flow through the water to ground, if a ground is available. In a lake, someone could be between the electrical source and earth ground. In a pipe (like a well pipe), you would not expect someone to be between the electrical source and earth ground.
 
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