Solar water well problem
Friday, July 18th, 2008
Jeff:
I have a solar water well in my pasture for the cattle, which was really great last year when we had the drought. this well was on the property when we bought it and now it has quit working, we’ve cleaned the panels and the wire but it still is not pumping, any suggestions?
Thank you
Susan Jones
Susan:
We have designed and installed many of these systems for local farmers and the biggest call-backs we receive is due to cattle destroying the float switch in their drinking tank or the wires to this float switch. This would be the first thing to check as most solar water pumping systems have some type of control to turn them off when the tank they are filling gets full. Also, some drilled well pumps have a float switch near the pump elevation is they are slow re-fill, to protect the pump by shutting it off if the well water gets too low.
Since a solar panel is fairly durable, these float switches are usually the problem with these systems. Most solar pumps have a controller mounted nearby to boost the current from the solar panels to avoid stalling out the pump at low sun conditions. If you can access this controller, it will have clearly marked terminals for the float switches and if there are wires to these terminals, then you have these switches connected and this is where you can either remove these wires (one at a time) or “short” out across the terminals where a float switch was connected to simulate the float switch being “open” or “closed”. This will tell you which float switch is bad or the wires are broken or shorted out. Of course I am assuming this is a low voltage DC system and you take proper safety measures.
While at the controller, most have a small LED light that indicates if the solar panel is providing power. If not, check with a volt-meter on both the wires coming from the solar panel to this controller, and the wires leaving the controller to the pump, to make sure the controller has not failed.
If all this checks out, the final check is the pump. Many small DC solar pumps will fail in about 6 years (although our deep-well DC solar water pump has been working for 14 years so far without a problem). Most of the better brands have replacement kits you can order parts to re-build yourself if the pump has failed.
I am assuming your system does not have a battery and just operates the pump during the day when the sun is up. If you do have a battery, these rarely last over 3 years in outdoor applications due to major temperature swings and may need to be replaced. However, very few solar pumping systems use a battery.
Hope this helps, let us know how it goes…..
Jeff Yago
