12 Volt Pump Recommendations?

System
System Posts: 2,511 admin
Hello,

I'm new to this forum and also to working with solar power. I'm trying to help my uncle trouble shoot a faulty water system at his island cottage. The cottage is in New Hampshire and has solar panels installed on the roof. These charge a bank of batteries which provide power to the water system.

The water system draws from the lake which is approx. 10 ft. from the house. We have been using 2 Wayne 12V, 14 Amp Transfer pumps, Model 57716-WYN1. These pumps have been piggy backed to lift the water, one placed about 8 ft. from the water and the other approx. 10 ft. further where the piping goes up about 15 ft. to a 55 gallon drum and 30 gallon propane water heater. According to the specifications for these pumps, they should pump approx. 200 GPH when lifting 15 feet but even when the batteries are fully charged we have a hard time getting enough pressure to pump up to the tank.

It is possible that these pumps were damaged or improperly winterized but if they need to be replaced I want to make sure we are getting the right pumps for the job. My technical knowledge as far as the solar system is limited but I'm happy to answer any questions that I can. I have read some great collective knowledge about off the grid systems on here and am excited to see if I can get some good information to fix this problem. Thanks in advance for all your help! :D

Comments

  • rplarry
    rplarry Solar Expert Posts: 203 ✭✭
    Re: 12 Volt Pump Recommendations?

    Well the reason no one else has answered your question is that there is no easy ans. I would first check the voltage to the pumps. If that is good then I would check to make sure that nothing is clogging the pump intakes. If that is OK then I would dismantle the pumps and make sure the diaphrams or impellors are not damaged and are working properly ( I couldn't find these pumps online so I don't know what type of pump they are).
    You didn't say but do the pumps seem to be running at the proper rpm, do they run at all? Let us know what you find.
    Hope this helps,
    Larry
    PS I use the shurflo pumps at my house here in Baja, and they hold up real well, last 5 years at least. I use the blaster, about $150
  • System2
    System2 Posts: 6,290 admin
    Re: 12 Volt Pump Recommendations?

    Thanks for your suggestions, Larry! I have checked to make sure nothing is clogging the lines. We did deal with the suction collapsing the hoses last year but this year we are installing reinforced ones to deal with that issue. The pumps do run but they lose prime often and they don't seem to have the power that they are supposed to have.

    I have passed along your pump recommendation and we may order one to try.

    Thanks again for your help!
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 12 Volt Pump Recommendations?

    I am wondering how well these pumps work with negative pressure on the inlet. I could not find any specs. either... But if the first pump is not designed to draw a vacuum on the input (or the pump is mounted too high above the water level)--its output can be severely limited. And adding a boost pump 15' (this is vertical feet, not horizontal feet?) will not help the first pump's reduced capacity issues.

    Try mounting the first pump (temporarily) near the water level and see if its output improves.

    You might be better off replacing the two pump system with one pump designed for the lift required for your use. Transfer pumps don't sound like they are really appropriate for the job.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: 12 Volt Pump Recommendations?

    Hi,

    Sorry about the hard time tracking the specs down. I copied the number down off the pump but it doesn't generate a productive search. Here's a link to the specs:

    http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200352044_200352044

    Thanks for all your help!
  • mikeo
    mikeo Solar Expert Posts: 386 ✭✭✭
    Re: 12 Volt Pump Recommendations?
    Sorry about the hard time tracking the specs down. I copied the number down off the pump but it doesn't generate a productive search. Here's a link to the specs:

    Thats an impeller pump and has no check valves. I use the 120 volt version for transfering wine from barrels and they are good for that. Look at
    http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_37142_37142

    I think that pump will do what you need and does have check valve built in. It is a demand pump and has good lift and will self prime if the pump if within about 8 ft of the water that you are pumping. I use this pump for garden and vineyard irrigation.
  • rplarry
    rplarry Solar Expert Posts: 203 ✭✭
    Re: 12 Volt Pump Recommendations?

    Mehera
    The pump you are useing is ( as mike says ) a rubber impellor pump. They are not known for their long life. The impellor wears out as does the shaft seal and the pump stops working well. The pump Mikeo referred you to is a good pump, I have used them also with good results. Here is another link for the shurflo pumps:
    http://store.solar-electric.com/shacdcwapu.html
    Shurflo and Flojet are very similar pumps, I would say that either one will do what you want to do, so which ever you find a better deal on, get it. There is a wide difference in prices according to how many gpm the pump puts out so make sure to get the pump that meets your needs.
    Larry