We've always said don't mix horses, electric and water, which is why we pass on electric buckets and water-trough heaters. These devices involve the horse, and no matter how safe or "untouchable" the electric portion may be, we worry that a persistent horse may get to it. However, if the horse is eliminated from the equation, like with a heated water hose, we'll try it.
We used the Thermo-Hose from K&H Manufacturing during a frigid Northeast winter. Temperatures dipped to below zero on many nights, but our Thermo-Hose never failed.
Available in 20-, 40- and 60-foot lengths, the hose has a thermostat that turns itself on and off, as necessary, to keep the water in the hose from freezing. it's designed to turn itself on when the outside temperature falls below freezing. It heats to just above freezing.
We plugged the hose in 20 minutes or so before use (instructions say 5 to 30 minutes), which was easy to do with all the other chores we have. We unplugged it when we finished watering, although the instructions state it can stay plugged in.
The hose stayed flexible during use and functioned normally. We used a spray nozzle at one end, so that we could walk from stall to stall without getting water on the barn floor - a potential ice-skating rink.
The plug-in portion of the hose is located at the faucet end. You'll need a GFI outlet (the outlets you see in modern bathrooms and kitchens that have a "test/reset" button on them). The GFI outlet functions as a safety device as it will shut itself off if it detects any moisture or an abnormal electrical flow. If you don't have a GFI outlet in your barn, do not use this hose. You shouldn't use it with an extension cord either.
The hose is not designed to leave under pressure for extended periods of time, so you can't leave it hooked up to your faucet. It also should not be kinked to temporarily stop the water flow, and you should protect it from traffic, like hooves, cars, wheelbarrows and even human feet. Remember, it has electric running through it, so you could damage the element. Coil it loosely between uses (don't use a crank hose reel). If you detect a leak, stop using the hose immediately. It has a two-year warranty against manufacturer defects.
This hose isn't designed for summer and must be protected from the sun. This is no problem for us, because at a cost of $92 to $145, we'll use an inexpensive garden hose during warm weather, to prolong the life of the Thermo-Hose (www.khmfg.com, 719-591-6950).
Frozen hoses are a pain. We've got the SolarTank to help with outside water, and now the Thermo-Hose can help you get the water to the tank.