Design Goals, Test Results and Veterinarian Comments

In order to get more people providing fresh water outdoors in winter we wanted to develop an animal safe system that was simpler to use than anything on the market and would work with our Solar Sipper solar water station.  The Water Warmer is a precision instrument with certain carefully engineered characteristics to benefit animals.  It is designed to work on flashlight size batteries, as they were convenient and available and withstand cold winter temperatures. It is self-enclosed to avoid all external wires and built with no sharp edges. It is designed to operate in an environment at 15 deg. F or higher with one quart of water. It is made to be portable so that it can easily be set up at any spot animals and birds favor in your environment.

The Water Warmer is designed to operate at low wattage and low heater temperature for safety. It is designed to require no ground fault devices or extension cords. It is also designed to be used in water containers of any material. 

By design, the Water Warmer provides just enough heat to keep water free of ice in very cold winter conditions, about 10 watts of power, or enough to keep a water hole free of ice but not enough to hurt animals or humans. Corded products generate very high coil temperatures for large amounts of water but the Water Warmer is specifically designed to provide just enough heat to keep a quart of water above the freezing point. In the Water Warmer, when the batteries run out, the unit slowly cools and some liquid remains open for a while longer.

The Water Warmer is designed to give about 2 hours of ice free water in very cold conditions using 2 disposable or rechargeable batteries in the Model One, and about 4 hours of operation (using our recommended batteries) with 4 batteries in the Model Two, and about 8 hours of operation in the Model Three All Day version.

The following test is representative of the many tests performed on the Water Warmer. It was conducted at night (no sun!), at about 11 degrees air temperature, in a one and a half quart dog dish with two (2) 8.5 Amp-Hr NiMH batteries.

The Dog Dish with the Water Warmer in it stayed liquid for about 2 hours. The control unit (no heater) froze over completely in less than 30 minutes. This was in a night test at 11 degrees F! At higher temperatures the unit will run for longer periods, about 2 hours or longer (depending on batteries used) at 15 degrees F air temperature.

Water Warmer in Dog Dish at 60 minutes – completely ice free	Water Warmer in Dog Dish at 1 Hour 40 minutes – some ice	Water Warmer in Dog Dish at 2 hours – ice skim complete
Blue = free water White = ice	Blue = free water White = ice	Blue = free water White = ice

Live Tests from the Vet

The Solar Sipper Water Warmer was tested by Dr. J. Robert Denk of the Commonwealth Veterinary Hospital in Newton Massachusetts in February 2006. Dr. Denk used the Water Warmer in water bowls for dogs in an outdoor run at the hospital, on a number of days where the temperature ranged from 24 to 30 degrees. It should be noted that even though the Water Warmer was designed to operate as low as 15 degrees air temperature, most dogs are not left outdoors for long periods at those temperatures.

Dr. Denk tested the unit on a Terrier, Labrador, Shepherd, Beagles, Dalmatian and a Poodle. These dogs ranged from 6 pounds to 75 pounds. Across the temperature spread noted above, the units kept the water ice free from 3 to 6 hours.  The dogs had no adverse reactions to the units in the bowls and drank normally throughout the tests. There was no biting, no playing with the units, or any harm to the dogs at all. Dr. Denk noted that the unit was safe, and "never hot to the touch."

Additional outdoor water test results and detailed veterinarian findings are available here: www.solarsippers.com/more_results.html.