Need help locating a 12 vdc water pump (low flow / high head)

TheyCallMeDave · 07-18-11, 09:14 AM

Im trying to find a lower cost , continuous duty, 12 v. water pump that will give me around 1 gpm at 40 feet of head for my solar hot water system im building . All the pumps on Ebay are not suitable. Thanks.

Ryland · 07-18-11, 12:27 PM

Google

I've used the El Sid pumps on solar hot water systems, even tho they cost a bit they are well worth it because these pumps do not fail and a pump that fails can destroy other parts or cause damage that will cost you more then a decent pump.

Other option is to go to an RV shop and get a pump for RV plumbing, but there is a pile of broken ones at my parents house for a reason.

Daox · 07-18-11, 01:36 PM

Unfortunately, the el sid pumps only go up 3.5 ft, and he needs 40 feet! Thats quite the vertical rise.

Do RV pumps handle SHW temperatures?

TheyCallMeDave · 07-18-11, 02:24 PM

Quote:

Originally Posted by Daox

Unfortunately, the el sid pumps only go up 3.5 ft, and he needs 40 feet! Thats quite the vertical rise.

Do RV pumps handle SHW temperatures?

Heres what i have :

a 300' coil of Pex tubing that is standing on end and has 12 turns ...so do u count each turn since it is vertical ? If so, then, I have 12 turns each at 2' high plus a 10' vertical lift from the collector to where the water heater is . ...or, 34' total.

(I dont have enough room to lay the Pex coil horizontal without building a whole new box from scratch)

trikkonceptz · 07-18-11, 02:30 PM

I don't know if this will help, but I would investigate Bilge pumps for boats. They may provide a solution for you and they are 12v

Daox · 07-18-11, 02:43 PM

Quote:

Originally Posted by TheyCallMeDave

Heres what i have :

a 300' coil of Pex tubing that is standing on end and has 12 turns ...so do u count each turn since it is vertical ? If so, then, I have 12 turns each at 2' high plus a 10' vertical lift from the collector to where the water heater is . ...or, 34' total.

(I dont have enough room to lay the Pex coil horizontal without building a whole new box from scratch)

Ooooh, yeah you don't need 34' of lift. You just need measure the disance between the water level at rest, and the very top of the solar collector piping. So, this looks to be ~12ft.

Also, if this is a pressurized system (vs dainback), there is essentially zero head and you only have to account for pressure loss due to the piping and fittings. In that case, you could probably get away with the el sid pump since pressure loss across 300ft of 3/4" pex really isn't that much.

TheyCallMeDave · 07-18-11, 02:53 PM

Quote:

Originally Posted by Daox

Ooooh, yeah you don't need 34' of lift. You just need measure the disance between the water level at rest, and the very top of the solar collector piping. So, this looks to be ~12ft.

Also, if this is a pressurized system (vs dainback), there is essentially zero head and you only have to account for pressure loss due to the piping and fittings. In that case, you could probably get away with the el sid pump since pressure loss across 300ft of 3/4" pex really isn't that much.

Ok, good., glad i told you ALL the details. Thanks. Ill look at El Sid.

Ryland · 07-18-11, 05:30 PM

The only time you are going to need a pump that has more then a few feet of head is if you are doing a drain back system and those tend to be complex enough that it's not really worth the little bit of savings you would get by not having to buy anti-freeze.

TheyCallMeDave · 07-19-11, 09:10 AM

Gottcha. Thanks.

TheyCallMeDave · 07-19-11, 09:52 AM

I just ran across this new hi temp. hi volume pump on Ebay and it looks like it would be super for my solar project : 350GPH DC12V 80'C Brushless Magnetic Oil Water Pump | eBay

Looks like a h.d. Industrial Pump with a low 1.8 amp draw on 12 vdc . Im very inclined to try this. Check out the specs on it. Any thoughts, concerns, tips ?? Thanks again.

07-18-11, 09:14 AM	#1
TheyCallMeDave Helper EcoRenovator Join Date: Jul 2011 Location: Far northern FLorida Posts: 43 Thanks: 0 Thanked 9 Times in 7 Posts	Need help locating a 12 vdc water pump (low flow / high head) Im trying to find a lower cost , continuous duty, 12 v. water pump that will give me around 1 gpm at 40 feet of head for my solar hot water system im building . All the pumps on Ebay are not suitable. Thanks.

07-18-11, 12:27 PM	#2
Ryland Master EcoRenovator Join Date: Mar 2009 Location: Western Wisconsin. Posts: 913 Thanks: 127 Thanked 82 Times in 71 Posts	Google I've used the El Sid pumps on solar hot water systems, even tho they cost a bit they are well worth it because these pumps do not fail and a pump that fails can destroy other parts or cause damage that will cost you more then a decent pump. Other option is to go to an RV shop and get a pump for RV plumbing, but there is a pile of broken ones at my parents house for a reason. Last edited by Ryland; 07-18-11 at 12:34 PM..

07-18-11, 01:36 PM	#3
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Unfortunately, the el sid pumps only go up 3.5 ft, and he needs 40 feet! Thats quite the vertical rise. Do RV pumps handle SHW temperatures? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

07-18-11, 02:30 PM	#5
trikkonceptz Helper EcoRenovator Join Date: Jul 2010 Posts: 44 Thanks: 3 Thanked 1 Time in 1 Post	I don't know if this will help, but I would investigate Bilge pumps for boats. They may provide a solution for you and they are 12v

07-18-11, 05:30 PM	#8
Ryland Master EcoRenovator Join Date: Mar 2009 Location: Western Wisconsin. Posts: 913 Thanks: 127 Thanked 82 Times in 71 Posts	The only time you are going to need a pump that has more then a few feet of head is if you are doing a drain back system and those tend to be complex enough that it's not really worth the little bit of savings you would get by not having to buy anti-freeze.

07-19-11, 09:10 AM	#9
TheyCallMeDave Helper EcoRenovator Join Date: Jul 2011 Location: Far northern FLorida Posts: 43 Thanks: 0 Thanked 9 Times in 7 Posts	Gottcha. Thanks.

07-19-11, 09:52 AM	#10
TheyCallMeDave Helper EcoRenovator Join Date: Jul 2011 Location: Far northern FLorida Posts: 43 Thanks: 0 Thanked 9 Times in 7 Posts	I just ran across this new hi temp. hi volume pump on Ebay and it looks like it would be super for my solar project : 350GPH DC12V 80'C Brushless Magnetic Oil Water Pump \| eBay Looks like a h.d. Industrial Pump with a low 1.8 amp draw on 12 vdc . Im very inclined to try this. Check out the specs on it. Any thoughts, concerns, tips ?? Thanks again.