No this product should not be in close contact to water or get wet. Also I don't think it would have the power needed to do what you are asking. Granted I don't know where you are there fore I don't know how much energy you will need, but I do have a hot tub and live where it gets cold and snowy so this might help you. My hot tub heater is 7.5 Kilowatts. And the tub holds 300 gallons. That means the heater in the hot tub has over 16 times the heat hot put of this heater. My point is this , how much heating capacity you will need is knowable. Its a math problem. You would need to know the volume of water and what you expect the coldest temperature to be. Then assuming you start with water that is 85-90, you would know how much heat it would lose and there fore how much you would need to put back in to maintain that temp. The answer will most likely be in BTU's. As there are 3413 BTU in a Kilowatt you can then turn the BTU answer into KW's which is a more common way of measuring electricity. Or better yet if you call a local farm supply store in your area they may have some quick rules of thumb that work well based on the average weather in your area.
As noted in the specification sheet this unit runs on 120 Volts and draws 4 amps. So you would need to wired it to a solar system that can produce that either directly or through an inverter.
I would not hang it and I would be very careful as it does get hot.
I am sorry but I am not sure if that is a question or a statement. So in case it is a question I will pontificate. Many people ask me about the efficiency of electric heaters. The fact is they are essentially 100% efficient. Pretty much all the electricity you buy is turned into heat. Each kilowatt of electricity has 3413 BTU's worth of heat when sent through a resistance heater. So at 450 Watts this unit will draw a little less than a half a half a KW an hour. Or 1535 BTU's of heat output. It draws small amount of power because it is a small heater. Larger heaters will draw more power but put out more heat, but always in that same equation of 3413 BTU's per KW
Yes you can. However keep it mind that when plugging in a heater or any devise that might draw significant current you don't want to use an extension cored if you do not have to. When you do you should try to keep it as short as possible and it should be of a substantial gauge. If an appliance draws more current than the cord can supply the breaker and or GFI is apt to blow,
This heater is used in agricultural and commercial applications where an exposed element is needed. I have seen it most frequently used on farms. It is placed under a metal watering stand. It heat conducts through the stand and keeps the watering troth from freezing. I have also seen it used in well houses in some cold climate states to prevent a well head from freezing. Because the element is exposed you would never use this heater in side a home.