We did a lot of shopping around for the best fountains for our barn. We live in Minnesota so we need fountains that don't freeze and don't leak. When we researched fountains, Nelson's fountains were advertised as being indestructible and wouldn't freeze. And a lot of zoos installed them, so if they were good enough for zoos, then we thought they would be good for us.
We were dooped! We bought 5 Nelson fountains; 1 outside stand alone model, and 4 side by side, stall mounts. We had them professionally installed by a plumber, but from the first day, they leaked, and they were extremely difficult to set up.
The problem with the Nelson fountain is you need to have baby hands to work on them. The inside of the guts of the fountain are burried inside, so you can't adjust them to fill the bowl for your horses. Every time you want to adjust them, you need to take out the bowl, and spill all the water onto the hot plate and electrical box. It's a miricle i've never been electricuted.
The Nelson fills by tipping a bowl back and forth and when the horse drinks, it tips back until the water fills it up and the weight of the water in the bowl tips it and shuts off the valve. This is a major design flaw because there is virtually no adjustment to the way it fills, and the level of water you want in the bowl. In the winter time, you don't want the bowl filled because it will freeze much easier because the water can't get hot enough.
And then there is the crappy valve that nelson uses. It's a plastic "pin" type valve that sticks and you need to keep it lubricated with Valseline. I called down to the "Technical Support" and I was pissed off that my fountains were leaking all over my stalls, and the guys said I needed to lube the valve with Vasaline. Are you kidding me? $600 bucks for a fountain, and Vasaline is what makes it work?
Then the guy said my water is to hard for the fountain to work properly. We live in the country, like 98% of horse barn owners do and everyone's water is hard. Apparently they never designed their valves and system to handle hard water.
Needless to say, I hate my Nelson fountains. If this story helps anyone who is thinking about installing one, please don't! Buckets and pails are much less hassel, and much less expensive.