Water Warmer Very Easy to Use No any pool heater are required, just immerse in water at proper level. plug into any grounded wall outlet. Check power indicator light in plug to make sure unit is on. then the immersion heater for water can automatically start heating, easy to use without complex steps. Widely Application pool heater for above ground pool Our bucket heater with thermostat, you can have a wonderful hot shower, wash your pets, heat your farm animals'water in winter, awesome camping necessity, heat a small pool, use for construction industry, animal husbandry, car washing, indoor use and many other jobs in cold weather. (Please note that when heating the water in your mini swimming pool or large bathtub, please use multiple immersion water heaters at the same time) The immersion water heater is rated at 2000W and operates at 110-125V AC. Water Warmer design with good thermal conductivity. pool heater for above ground pool will quickly heat 5 gallons of water with high power in a few minutes(longer in winter).If too much water is heated it takes more time or more than two products are used at the same time WARNING:When using the immersion water heater , first put the water heater into the water, be sure pool heater for above ground pool to ensure that the water heater is fully immersed in water, and then plug in the socket. Determine the operation sequence to effectively prevent fire.