So yes, they are electrical machines, but they don’t have a resistance heating element as you might find in a electric stove top or a electric element domestic hot water heater. A large heat pump might use 6 KW of power and hour and give you 120,000 BTU's where an electric element heater might use 20 KW and give you only 68,000 BTU's. Electric swimming pool heaters do have a heating element. Most are used for small spas as you are heating maybe 500 gallons instead or 20,000 gallons. They are also used in baptismal tubs or baptisteries. It is fine for that purpose as the amount of water is small. The cons of this type of heating method for larger amounts or water is that the heating element draws a lot of electricity, making it very expensive to operate. It could be OK to temporarily heat a small spa but a swimming pool has such a large volume of water to heat, that most of the time it doesn't make financial sense. Another disadvantage with electric element heaters is that they will not tolerate chemical or PH imbalance in a swimming pool as most are not made from titanium as heat pumps are, and the metal that is in contact with water in an element heater can be damaged, especially if you have a salt based swimming pool sanitation system.
These element heaters can also known as electric pool tankless heaters. Their initial cost is very economical compared to an electric swimming pool heat pump but in the long run they will be much more expensive to run than other pool heating methods such as heat pumps, solar and natural gas heaters, and as a result might not be used much and the pool will not be comfortable most of the time. If a heat pump costs you $100.00 a month to run a tankless (or element) heater might cost $500.00 to $700.00.
While doing your pool heating research keep in mind the difference among both pool heaters. If you have any questions please give us a call. Our number one goal is to find the right equipment to your unique installation.