For the good use of kerosene heater, you should choose good quality kerosene fuel when selecting it, but how do you test the quality of kerosene fuel? The best way to evaluate the quality of kerosene is through visual inspection.
Siphon a small amount of kerosene from the bottom of the container, where it is mostly water and particulate contaminants. Place the sample in a small clear jar and let it sit for at least an hour, then look through the fuel to see if there is anything floating, such as particles or bubbles, which are a sign of water contamination. The fuel should be clear and transparent with no separation. Note that anything cloudy or yellowish is contaminated and should not be used. While red fuel is harder to see contamination, it should be translucent like Kool Aid, not cloudy, opaque, or dusty.
The final test is to burn the kerosene heater. The flame should be bright and even. Any kerosene odor should become very faint after the heater reaches optimal burning conditions (45-60 minutes).